Just knowing my fundamentals and circuit designs, I knew it couldn't be anything else. And now that you've been studying and taking my ScannerDanner Premium classes, this kind of thing will start making a lot more sense. It's cool to see you eating this stuff up man. You are doing exactly what it takes my friend. Thanks for giving me a chance !
I'm really enjoying the basic electrical concepts review section. Quality instruction on the Internet ( or anywhere else for that matter ) is hard to come by and I'm glad to have stumbled across your channel and then your premium classes.
Fuel pump is a electric motor. idk wtf is wrong with mine. its been running lean and sometimes turning over and not starting. Fuel pump not priming. It finally quit all together. I assumed the pump went out since its 1999 f150. Ive put a new one in and its still not coming on to prime. I got 10v at the pump but my ground wasn't from battery. The Audio, GEM, PCM fuse was blown. All others good.
This video solved my problem man. I owe you one! My fuel gauge was stuck on full and My truck is a ranger too so I checked the connectors in the same spot under the truck and found 3 broken feed wires. One of them was the sender assembly circuit. Spliced them the same as yours. No more counting miles till empty! Serious bro, thanks again
@foxholewilly Yes it was a ground to ground voltage drop test and if I could have shown the wire before the break it would have been identical voltage as at the ground point I showed. As far as using piecing tools, I try not to do it but I had to in this case. When I am done (depending on location of the wire) I will use a small amount of RTV. I never heard about RTV being a problem but I am no chemist so maybe it is? I don't get overly concerned about it though.
at the 7:38 mark the meter shows around 10.7 volts on the Ground circuit! this means that if we had 14+ volts on the pump feed (which would be normal battery voltage with the engine running) and 10v on the pump ground, that there is only a 4 volt difference in potential. So essentially the pump was running on 4 volts at that point. (remember system voltage with the engine running is 14 not 12, I think that is where some of your questions will be answered) let me know if this helps
Your channel has been very helpful so thank you for the uploads! My ranger starts to run rough and stalls after reving it past 2800 rpm. All plugs get spark and I have changed spark plugs, fuel filter, air filter, cleaned IAC MAF and throttle body yet the problem still persists..
This is great! I never would have expected those two to be tied in together either and was very confused at the beginning of the video. Now it all makes sense and I've learned something today. Thanks!
@HaroRider03088 Followed the harness as I showed in the video. Did a visual inspection and voltage drop test. If I wouldn't have seen the problem visually I would have started testing that wire (same voltage drop test) in different locations to identify where the problem was.
Mitchell gives this wide range because some of these Rangers used an electronic returnless system where the PCM controls pump RPM to control psi. Those systems had a wider range of operation.
@gmtech4327 Thanks for the heads-up. I had no idea. I will get some of that Liquid Electrical Tape. I've seen it before, just didn't think about using it for that.
Today I had a 2011 Malibu 2.4 with a intermittent crank no start. No code's, couldn't duplicate, but definitely believed it was happening because the customer put a ecm, fuel pump and fuse block in it. That eliminated a likely component failure. I pulled up a schematic of the fuel pump relay located in the trunk and and noticed the grounds were shared with a majority of the interior lights and rear lights. I asked the customer a lot of questions of patterns he see's when the car acts up. He said the lights flicker when it happens. The lights are shared on the same ground for the fuel pump relay signal ground and the rear defogger too. I toggle the brake lights and defogger on, and duplicated my dome lights to flicker abnormally. I checked that ground with engine running, it had a 1.2 voltage drop from battery negative. Finally got a good direction and theory of what causing that fuel pump to lose power. I couldn't help notice the terminal ground on the front strut tower had the same voltage drop reading so eventually I realized I had a bad body ground. Pulled up engine cranking schematics. Found the 2 points where the negative cable branch out. One to engine and one to body. I load the ground with my uactivate jumping the starter and that body ground terminal started getting very hot. Bingo! Terminal fretting or some kind of air gap in between the terminal and body. Needed a prybar to get that terminal off. Look forward to cleaning it up and retesting tomorrow. That fuel pump was probably getting up to a 6 volt drop when all accessories are on. I watched this video 3 months ago and it gave me good direction to find this problem. Only advise Paul may have not mentioned on screen is I recommend really digging in a ground terminal when testing. I was getting false readings today that threw me off. Normal false voltage when touching the terminal. Abnormal true voltage when scraping the terminal with the multimeter test probe.
@contagiousFX I generally do not use the fuel trim numbers when I have a misfire. Unless of course the misfire is from a vacuum leak where the fuel trim would be very positive. Most of the time a secondary ignition misfire does not mess with the fuel trim numbers too bad.
Great video, its giving me a starting point with the same exact problems. Using any electrical (headlights,reverse lights, brakelights, signals) all drop my fuel pressure from barely running to kiling the engine if I turn on enough lights. Found a charred/burnt plug with a bare wire going into it at the fuel inertia switch. Repaired it and unfortunately I'm still having the same problems. It's too bad you aren't local, I'd just bring it to you. I don't trust any of the mechanics around here.
ScannerDanner is the best I saw in the internet. I wish I have a mechanic like him because around where I live when you have a problem in the car at the end you get a new car!! I have a problem in the moment that already made me spent some money and still there... Now the dealership told me: we have to change this and that... and I have to pay for it! This is crazy around here!!!
Yet another awesome trouble shoot Paul ! I have extensive background in Electronics..as i am a Technician (Consumer electronics) . I understand your trouble shooting flows like the back of my hand...and they often take me back to when i was doing my Electronics course . I love them ! Keep up the awesome diagnostics Paul .
@contagiousFX Neither as the car was fixed. If I didn't reset the memory the STFT would go negative to counter the LTFT command. This would only be temporary as the LTFT would relearn.
@fivefortyeye540i If you had a dead coil (two cylinder misfire) on a 4 or 6 cylinder engine, it would be running so rough (especially the 4cylinder) that I would immediately do an RPM drop test to figure out which cylinders were dead. I don't think I would even look at trim. However if the misfire is severe enough you will see positive fuel trim numbers. Keep in mind, in a case where the PCM is intentionally shutting off the injectors that this may affect normal fuel trim corrections.
@ScannerDanner However if the owner drove that car that way for a long time, the unburned fuel in those two cylinders would end up also in the crankcase and cause fuel contaminated oil. This will get picked up by the PCV system and drive the fuel trim negative.
i learned alot from this vid.. i never would had thought to check the ground side.. i woulda been scratching my head.. probaly would had thought fuel pump was bad.
@fivefortyeye540i First, unburned fuel is not "rich", it is simply unburned fuel. Also the misfire does not consume the oxygen that was in that cylinder either. This drives the O2 lean. I have never seen a misfire cause negative fuel trim numbers. As for a dead coil on a waste spark goes, they are known to fail with heat so maybe the coil was firing on start-up. My guess is your negative LTFT numbers were not because of the misfire....
Fantastic amazing job , my 1998 Taurus was acting similar to that ranger before It quit running completely. I need to go check for a bad ground before I tackle the FP.
@ScannerDanner Some RTVs will contain ammonia, that is the vinegar smell. Ammonia is corrosive. I usually seal wires with Liquid Electrical Tape, comes in a small can with a brush in the cap. Easy to use.
Awesome work once again my friend. Keep it up. Love your videos because they always appproach from the modern tech side if you will. Nice change of pace from traditional methods.
@scannerdanner Let's say for argument sake that a coil was not firing( at all )on a gm waste spark system. The ECM in response to that would take fuel away, thus showing (double negative ) longterm fuel trim to protect the catalytic converter ??
"parts changers" suck don't they? Unfortunately it is the norm in my field. I'm going to go out on a limb here and say that of all of the mechanics out there, only 5-10% of them can actually do proper troubleshooting. It's horrible for car owners but great for the guys that can actually fix these cars. They can almost name there price wherever they go.
the first thing I would do with that is address the 80 pounds of fuel pressure problem first. this is way too high for that system. with that kind of fuel pressure you should have rich conditions not lean conditions but in any case fix ur fuel pressure problem first
Awesome video.I was wondering the result was the same(bad pump ground), if you would have diagnosed the P0232 fuel pump secondary high Instead of the lean codes. Thanks you are the man for the job
gread video.. i nver thought of checking ground wires since my 84 ss is acting up but once i disconnect the fuse to the ecu it drives great but rich. unfortunately, once plugged in it has a rough idle when ever it wants, and I mean rough. thanks again.
Does a 1992 Ford Ranger 2.3 liter 5spd p/u have a fuel safety cut off switch? I believe when pump is bad, however when its warm out (above 50°F) she starts right up. In winter (Baltimore Maryland area) it'll crank & crank & eventually catch & the truck will run fine all day after that. The other day while driving, hit a bump & she started to run like it's fuel starved.
Hello Paul. I'm curious how a ground wire could corrode and split when it's untouched and inside a plastic loom. It must have been chafing on a metal edge.
@scannerdanner. So it is not possible for long term fuel trim to read rich do to unburned fuel within cylinders?? Have u ever seen a gm waste spark system with a dead coil whith (no dtc )?? And on start up the thing ran smooth?? Well I witness this on a another 3.1.. I did not do a snap throttle to load engine..my own ignorance. I just plugged scanner in to view fuel trim - 22 ltft .long story short first coil going left to right was dead, cylinder 2 and it's companion was not firing. On sta
My 87 ford ranger does not show the fuel level some people say it can just be a ground i also notice that whenever i try using my turn signals the front work well but the back ones both turn on at the same time regardless if i try to go just left or right both turn on. I have a misfire too can a bad ground cause also that?
wow man great how to. very knowledgable and i would have never tracked that bad ground down for those symptoms! you rock man, ill def check out your other vids! keep on doin what you do man!
I got a 99 mustang gt the problem is it smells like old gasoline every time i start my when is cold and it has bad idle but when is hot it works fine can you help me you think is the fuel pump
Dan,I enjoy your videos, they are very informative. I am concerned with your technique of wire piercing.That should only be done in extreme circumstances,when there is absolutely no other way to obtain a measurement. And then the piercing needs to be weather sealed to prevent a future corrosion failure.Sorry for the criticism but, the fact that you are so adept at troubleshooting conveys the message that this is an acceptable practice when really it is the cause of A future problem. I hope you address this in the future. Thanks Bob
I have a feeling this is whats wrong with my 94' c1500 chevy 5.7. Its running great except for on the freeway after 65mph+ for 5 minutes it starts to slow itself down and Im having a voltage draw issue making my new alternator whine, removing the rear single plug wire makes the noise go away and back again when plugged back in. My blinkers are causing a huge voltage drop when headlights and brake lights are applied at the stoplight.
@@ScannerDanner But its the 3rd new alternator ive put in in a week. NEW not rebuilt. I though they had bad bearings but its a voltage draw causing the whine and Im lost.
@@ScannerDanner 6 months ago I was on my way home from Lake Havasu on the 40 freeway. You have to have your headlights on when you leave Havasu on the 95 for daylight. I forgot to turn them back off after I got on the freeway and after an hour or so I started losing speed then truck died. Waited a few minuted then back on the road but it did it again within 5 minutes. Over and over until it finally quit, dead battery. Had it towed and the mechanic said he had to put a new battery cause old one wouldnt hold a charge, and that he had to put a fuel filter in to. Wouldnt turn over until the new battery then wouldnt start till the new filter was in, then it ran again. I drove it to Havasu one more time with no issues, but after I got back it started to do that to me on the freeway on my way home at night and has been doing it every single night for the last 3 months. Another new battery didnt help, and the origional alt started to go bad, the battery alt gauge was dropping as I was driving, replaced the alt and no more drop but the new alternator were whining. Old one wasnt. Unplugging the F(field) wire from the back of the alt make the whine stop, then returns when plugged back in. There must be a draw on that field wire. Im thinking there is a bad ground to my dash/ignition system, causing the fuel relay or pump to overhrat while on the freeway???? Last night I had to use my wipers and they were weird, running a few times then stopping for a second then running a few times and stopping again, slowed a bit then speed back up. When I turned on my headlights to leave work my sterio quickly cut out but was still working. Ground?????
Ive spent over $1500 over the last 2 months on mechanics/ diagnostics/ parts, Ive done research, asked around and cant get anywhere with this issue. Ive put in a new fuel pump, filter and injectors. A new Battery, throttle pos sensor, O2 sensor, ignition control module, MAP sensor, EGR valve and still have no joy. Last week I had the fuel pressure tested and the trans tested, both passed. No water in my oil or oil in my water. Fluids are all full and clean.
I had the same thing happen on a Toyota Camry 6 volts was dropping on the ground side of the fuel pump. But it would only happen when you applied the brakes.
Do you know if they changed the way this was routed in the 2002 model? I'm working on a 2002 Ranger XLT. According to advanced autos scanner its throwing 33 codes! My cheap harbor freight meter grabbed 11. Everything from miss firing to transmission codes. When driving it dogs bad, like it's starting out in 3rd and never shifts, itll sit around 3 grand on the highway. I can manually shift it down to 2nd but not first. I'm guessing it's a 3 speed with overdrive.
paul, just to make sure i understand, at 7:25 we see 4.62v. does that mean the pump is only running on 7.38v? when you turn the parking lights on we have a reading of 10.7v. so doesnt that mean that the parking lights, pump, and signals are running on 1.3v? the reason i ask is that at 7:35 you mention the pump is running at 4 volts. dont you mean 7.38v? i can very well be wrong.
Wow!!!!! God bless!! I can tell you were finally happy finding the problem. I have a problem with a crank but no start on my 2006 VIN#U Ford Ranger 3.0 V6. Can u give me any information that would help me?? Would the Ford Company be able to diagnose it if I tow it to them? Because one garage couldn't diagnose?? But it was a Tire shop where I had fuel pump put on. Willing to pay good money for information
Let's find you a shop in your area that is using SD Premium for training for their technicians. Use this directory and if there isn't one close to you yet, there hopefully will be someday. scannerdanner.com/find-sd-shops.html
I have a question for you if you wouldn't mind giving me some insight. (2001 ford ranger 3.0l -----15,000---- miles 2wd automatic return less fuel system fuel pressure is 68 koer koeo (extreme rich condition is the problem)) customer just put a new fuel pump in it because of bad check valve. problem existed before the new fuel pump, there was another pump put in it by the previous owner before the one yesterday, odd but this is the history I have on it. anyway the fuel trims are going lean 24% stft b1 and b2 ltft goes to about 6-8% negative b1 b2 before pcm kicks it out. if I create a huge vacuum leak like the booster line I can get the truck to start using trims. pcm fuel pump command is 100%? if I command the the pcm to have 40% duty cycle the pressure drops to about 37-40psi and the trims come back close to normal and the o2 sensors are reacting normally. the truck will negative trim the fuel until the pcm kicks it out and goes back to 0.0% trims across the board until reset. this truck ate 10 gallons of fuel in 80 miles please text me or call at 636-368-8267 or email at ghenke@hotmail.com. love your videos and have purchased your e book. there aren't too many cars I cant figure out but this one has really thrown me for a loop. thanks in advance Jerry Henke @ Alternative Auto Winfield MO
Can something like this stop my fuel pump form activating ? Like when I go to start my ranger it just cranks but doesn’t start so I changed the fuel pump and made sure the inertia switch in an it still doesn’t turn on the pump please help
Ok, PVC contamination is very logical more then likely that is what happened.. I would have never thought about that.. I have a mental note of it now..
Have a similar issue on '11 f150 6.2 v8. Trouble starting, left power running board not going down, driver seat not moving up or back, left tailgate lightbar all not working properly at intermittent times and not at the same time. Is there a place that isn't too expensive or free to get good wiring diagrams for my truck?
www.scannerdanner.com/forum/post-your-repair-questions-here/16-need-service-info-check-here.html We've created a thread on my forum to help you guys with this. Thanks! It's free to join.
Great video Danner! I would like to see some real nightmare case studies like I get over here in the ghetto of south Kansas City! Lots of cars with backyard mechanics destroying things. Customers bring the cars to me with very little if any info about what the moron parts changer did!
@scannerdanner I have a 2000 Ford ranger 3.0 flex fuel with 101k miles on it I have a intermittent code that's says p0176 flex fuel circuit can I can advice on the test or diag the issue without a o'scope?
+Xrio Sankara not sure off hand on that sensor. I think it is a frequency generating device. Post this question on my forum. I'm sure my guys over there can help you with some great details. www.scannerdanner.com Thanks!
dan bleeck no spark on this system is usually either the pick-up coil in the distributor or the ignition module. I have a video on testing an ignition system with a test light that I will be unlocking in a day or so that will really help you. In the mean time watch this one. th-cam.com/video/mDKj19Hnhd0/w-d-xo.html
hey great video dude , I have a f=different problem maybe you can answere , a 2007 ranger sport with a replaced motor of 61 k ,,,,,,,,,,,,, I was getting poor acceleration and hesitation . the scan read faulty bank 1 and 2 sensors , so I replaced them they were old and original and still have the same reading and hesitation . oddly , the temperature gauge gets to the middle id say operating temperature in less than 2 miles or so , can this be sending a bad or no signal to the computer to go from open to close loop ., it seems to do it cold also , in fla so not frezzing cold lol ,,,,,,,,,,,,,,,, I find it odd it would raise the needle to the middle so quickly is all , and can that sensor just be cleaned . or checked ? and would a open loop come up in an obd2 scan with the rich o2 sensor readings ?
You need to take your truck to someone who knows how to troubleshoot. Oxygen sensor codes do not mean you need oxygen sensors. Sounds like a lean condition from your description. You also need to make sure the correct engine was put in. Some of these are flex fuel systems that use different injectors than the regular gas only engines.
Wow awesome video. Question should all fuel pump pressure be about 50 psi. I have a 04 jag 3.0 engine the x-type. The fuel psi is 27 is that ok. The car takes long to start sometimes.
This is a bit of a shot in the dark, and not sure if you are able to offer us any advice, but we have a Ranger, 2002, XLT, 2.5TD, which is lacking in power generally. We have replaced the cylinder head and turbo, and renewed all the filters, etc, but although it runs without misfire, etc, it just has no 'oomph' to it? Any ideas????
Hello. I have a 98 mustang GT. It has a slight misfire in 2nd and 3rd between 1500-2500 RPM. My fuel pressure with key on, engine off is 0 PSI, 29 at idle. I replaced the fuel pump, filter and the regulator. I am going to pressure test the fuel pump but I have a feeling it was something to do with the electrical components or the injectors. Any advice on this one? Thank you.
This sounds like a light throttle misfire with is usually a secondary ignition symptom. While it is certainly NOT normal for fuel pressure to drop to 0 when you shut the car off, this may just be a leaking pump check valve which will have ZERO affect on how the pump performs when the car is running. The only thing this would give you is a longer than normal crank time. There are other causes of fuel pressure dropping to zero on shut down that WILL cause some diveability problems (leaking injector, leaking psi reg diaphragm) but these will also cause fuel trim issues. Do you have access to a scan tool that gives you your fuel trim numbers? If you do, I need hot engine idle STFT and LTFT on both banks and then 3000 rpm, again, both banks.
Hello. Thank you for your response. I just data logged everything. Where should I sent the Excel spreadsheet with the data? at hot idle, STFT on bank 1 was between -1.6 and +1.4 and LTFT started at -4.7 and climbed down to -6.2 with time. On B2 STFT was around -2.3 and LTFT started static at -3.9 and went down to -4.7. At 3K RPM, on B1 , STFT was between -3.1 and -0.2 with occasional spikes up to +3.1. LTFT was static at -6.2. On B2 STFT was between -5.5 and -0.8. LTFT was initially -3.1 and then stabilized at -2.3. Before the tests when I turned key one, engine off on a cold car, I had 0 PSI and 29 PSI with engine running. Interestingly, when I turned off the car, the fuel pressure was 29 PSI and the pressure decreased at about 10 PSI per 20 min. I have a return fuel system so I don’t know if this is acceptable. During the second testing, on an already hot engine, I had 3 PSI with key on, engine off. Then repeated and the PSI jumped to 11 PSI and went I turned the key on the third time, it jumped to about 35 PSI. After I took out the key, the PSI dropped at about 2 PSI per 1.5 minutes. When I turned the car on with a hot engine, it again was 29 PSI. Gave it some snappy throttle and the PSI quickly went down to about 25-26 PSI and quickly came up to 29 PSI. With different loads at 1.5K, 2.5 RPM and 3k RPM, the pressure stayed at 28-29 PSI. Never went above 30 PSI. After I shut down the car, the pressure decreased by about 10 PSI in about 30 min. Also, my scanner was stating that the fuel system was in closed loop all the time. From the first till the last second of data logging. I started logging with a completely cold engine and in the end after pressure testing, even went for a short drive with an operating temp. Still it was showing that it was in a closed loop. Is this normal?I would appreciate any advice. Sorry for any confusing sentences.
hey scanner danner i have a 2002 ford ranger has misfire on cyl 2 and ive replaced coil pack wires plugs and we replacing plugs i found cyl 2 was broken lol but its has rough idle poor mileage and dam thing is power loss from heck and we all know they are called 3.slows so its worse than normal its only got 136.xxx miles any help be appreciated im running outta ideaas lol
as pressure drops when the headlights being turned on "check out the fuel pressure, that's awesome." don't know why, but I giggled a little bit on the inside.
I got a 2000 Toyota Camry P0304 P0171 P0500 I replaced Cam Shaft Sensor Crank Shaft Sensor MAP Sensor Cleaned the EGR EGR Modulator TPS VSS - I am Still getting the P0500 (I have a multimeter so I will test that) Radiator and thermostat PCV valve and grommet Timing Belt Plugs and Wires Used Lucas fuel injector cleaner X2 as well. I have a new knock sensor but I could not get the new part on because that is EXTREMELY hard to get the old one off The car will run for 15 miles then CUT OUT. The car will restart 45 minutes later but misfire BADLY. Something obviously is getting hot then killing the engine Help Me!!!
I meet a guy at spare parts shop, he has a problem with his car when he start the air conditioner, the car shuts off. Maybe it is the same issue here. Bad ground,, possible.
![How to Test for a Stuck Open Fuel Pressure Regulator! [A ScannerDanner Premium Lecture]](/img/n.gif)
At about 3:25 you said right off the bat that it must be a shared ground between the pump and headlights. Why was it immediately so obvious to you?
Just knowing my fundamentals and circuit designs, I knew it couldn't be anything else. And now that you've been studying and taking my ScannerDanner Premium classes, this kind of thing will start making a lot more sense. It's cool to see you eating this stuff up man. You are doing exactly what it takes my friend. Thanks for giving me a chance !
I'm really enjoying the basic electrical concepts review section. Quality instruction on the Internet ( or anywhere else for that matter ) is hard to come by and I'm glad to have stumbled across your channel and then your premium classes.
Thanks for giving me a chance!
Fuel pump is a electric motor.
idk wtf is wrong with mine. its been running lean and sometimes turning over and not starting. Fuel pump not priming. It finally quit all together. I assumed the pump went out since its 1999 f150. Ive put a new one in and its still not coming on to prime. I got 10v at the pump but my ground wasn't from battery. The Audio, GEM, PCM fuse was blown. All others good.
This video solved my problem man. I owe you one! My fuel gauge was stuck on full and My truck is a ranger too so I checked the connectors in the same spot under the truck and found 3 broken feed wires. One of them was the sender assembly circuit. Spliced them the same as yours. No more counting miles till empty! Serious bro, thanks again
That’s a smart customer made your job easier with their good description of the problem. I always appreciate these type of customers
@foxholewilly Yes it was a ground to ground voltage drop test and if I could have shown the wire before the break it would have been identical voltage as at the ground point I showed. As far as using piecing tools, I try not to do it but I had to in this case. When I am done (depending on location of the wire) I will use a small amount of RTV. I never heard about RTV being a problem but I am no chemist so maybe it is? I don't get overly concerned about it though.
at the 7:38 mark the meter shows around 10.7 volts on the Ground circuit!
this means that if we had 14+ volts on the pump feed (which would be normal battery voltage with the engine running) and 10v on the pump ground, that there is only a 4 volt difference in potential. So essentially the pump was running on 4 volts at that point.
(remember system voltage with the engine running is 14 not 12, I think that is where some of your questions will be answered) let me know if this helps
Your channel has been very helpful so thank you for the uploads! My ranger starts to run rough and stalls after reving it past 2800 rpm. All plugs get spark and I have changed spark plugs, fuel filter, air filter, cleaned IAC MAF and throttle body yet the problem still persists..
874 fire gas but will not run
This is great! I never would have expected those two to be tied in together either and was very confused at the beginning of the video. Now it all makes sense and I've learned something today. Thanks!
@HaroRider03088 Followed the harness as I showed in the video. Did a visual inspection and voltage drop test. If I wouldn't have seen the problem visually I would have started testing that wire (same voltage drop test) in different locations to identify where the problem was.
Just when you thought you've heard everything. Great work and explanation as always. Thanks!
It's a good idea to thank the teacher for this article.
Mitchell gives this wide range because some of these Rangers used an electronic returnless system where the PCM controls pump RPM to control psi. Those systems had a wider range of operation.
@gmtech4327 Thanks for the heads-up. I had no idea. I will get some of that Liquid Electrical Tape. I've seen it before, just didn't think about using it for that.
Today I had a 2011 Malibu 2.4 with a intermittent crank no start. No code's, couldn't duplicate, but definitely believed it was happening because the customer put a ecm, fuel pump and fuse block in it. That eliminated a likely component failure. I pulled up a schematic of the fuel pump relay located in the trunk and and noticed the grounds were shared with a majority of the interior lights and rear lights. I asked the customer a lot of questions of patterns he see's when the car acts up. He said the lights flicker when it happens. The lights are shared on the same ground for the fuel pump relay signal ground and the rear defogger too. I toggle the brake lights and defogger on, and duplicated my dome lights to flicker abnormally. I checked that ground with engine running, it had a 1.2 voltage drop from battery negative. Finally got a good direction and theory of what causing that fuel pump to lose power. I couldn't help notice the terminal ground on the front strut tower had the same voltage drop reading so eventually I realized I had a bad body ground. Pulled up engine cranking schematics. Found the 2 points where the negative cable branch out. One to engine and one to body. I load the ground with my uactivate jumping the starter and that body ground terminal started getting very hot. Bingo! Terminal fretting or some kind of air gap in between the terminal and body. Needed a prybar to get that terminal off. Look forward to cleaning it up and retesting tomorrow. That fuel pump was probably getting up to a 6 volt drop when all accessories are on. I watched this video 3 months ago and it gave me good direction to find this problem. Only advise Paul may have not mentioned on screen is I recommend really digging in a ground terminal when testing. I was getting false readings today that threw me off. Normal false voltage when touching the terminal. Abnormal true voltage when scraping the terminal with the multimeter test probe.
He already reminded us to check grounds. Duh
@contagiousFX I generally do not use the fuel trim numbers when I have a misfire. Unless of course the misfire is from a vacuum leak where the fuel trim would be very positive. Most of the time a secondary ignition misfire does not mess with the fuel trim numbers too bad.
Great video, its giving me a starting point with the same exact problems. Using any electrical (headlights,reverse lights, brakelights, signals) all drop my fuel pressure from barely running to kiling the engine if I turn on enough lights. Found a charred/burnt plug with a bare wire going into it at the fuel inertia switch. Repaired it and unfortunately I'm still having the same problems. It's too bad you aren't local, I'd just bring it to you. I don't trust any of the mechanics around here.
ScannerDanner is the best I saw in the internet. I wish I have a mechanic like him because around where I live when you have a problem in the car at the end you get a new car!! I have a problem in the moment that already made me spent some money and still there... Now the dealership told me: we have to change this and that... and I have to pay for it! This is crazy around here!!!
Yet another awesome trouble shoot Paul ! I have extensive background in Electronics..as i am a Technician (Consumer electronics) . I understand your trouble shooting flows like the back of my hand...and they often take me back to when i was doing my Electronics course . I love them !
Keep up the awesome diagnostics Paul .
Cuando sabes como funcionan las cosas no hay cosa extraña que te sorprenda. Gran diagnostico.
Looks like jack stand might squeezed it sometimes ago. Your trouble shooting skills is so great.
@contagiousFX Neither as the car was fixed. If I didn't reset the memory the STFT would go negative to counter the LTFT command. This would only be temporary as the LTFT would relearn.
Don't worry about shaky cam,still very clear and better than most put on here.
@fivefortyeye540i If you had a dead coil (two cylinder misfire) on a 4 or 6 cylinder engine, it would be running so rough (especially the 4cylinder) that I would immediately do an RPM drop test to figure out which cylinders were dead. I don't think I would even look at trim. However if the misfire is severe enough you will see positive fuel trim numbers. Keep in mind, in a case where the PCM is intentionally shutting off the injectors that this may affect normal fuel trim corrections.
crawled under a truck and let some guy start it ...
Paul you are crazy my man.CRAZY
@ScannerDanner However if the owner drove that car that way for a long time, the unburned fuel in those two cylinders would end up also in the crankcase and cause fuel contaminated oil. This will get picked up by the PCV system and drive the fuel trim negative.
i learned alot from this vid.. i never would had thought to check the ground side.. i woulda been scratching my head.. probaly would had thought fuel pump was bad.
@fivefortyeye540i First, unburned fuel is not "rich", it is simply unburned fuel. Also the misfire does not consume the oxygen that was in that cylinder either. This drives the O2 lean. I have never seen a misfire cause negative fuel trim numbers. As for a dead coil on a waste spark goes, they are known to fail with heat so maybe the coil was firing on start-up. My guess is your negative LTFT numbers were not because of the misfire....
wow, good find. I would have been mislead by the good ground at the eyelet.
Fantastic amazing job , my 1998 Taurus was acting similar to that ranger before It quit running completely. I need to go check for a bad ground before I tackle the FP.
@ScannerDanner Some RTVs will contain ammonia, that is the vinegar smell. Ammonia is corrosive. I usually seal wires with Liquid Electrical Tape, comes in a small can with a brush in the cap. Easy to use.
ScannerDanner, your videos are awesome and very helpful . Wish you lived closer in my area of New Hampshire.
Imagine if you did not have access to wiring diagrams. Great stuff Thanks !!
@CoolasIce2 Not sure bro
Awesome work once again my friend. Keep it up. Love your videos because they always appproach from the modern tech side if you will. Nice change of pace from traditional methods.
@scannerdanner Let's say for argument sake that a coil was not firing( at all )on a gm waste spark system. The ECM in response to that would take fuel away, thus showing (double negative ) longterm fuel trim to protect the catalytic converter ??
"parts changers" suck don't they? Unfortunately it is the norm in my field. I'm going to go out on a limb here and say that of all of the mechanics out there, only 5-10% of them can actually do proper troubleshooting. It's horrible for car owners but great for the guys that can actually fix these cars. They can almost name there price wherever they go.
the first thing I would do with that is address the 80 pounds of fuel pressure problem first. this is way too high for that system. with that kind of fuel pressure you should have rich conditions not lean conditions but in any case fix ur fuel pressure problem first
Awesome video.I was wondering the result was the same(bad pump ground),
if you would have diagnosed the P0232 fuel pump secondary high Instead of the lean codes.
Thanks you are the man for the job
excellent job Mr Paul. blessings for you and your family
gread video.. i nver thought of checking ground wires since my 84 ss is acting up but once i disconnect the fuse to the ecu it drives great but rich. unfortunately, once plugged in it has a rough idle when ever it wants, and I mean rough. thanks again.
Agree, it was definitely rubbing on something
sweet! nice job and thank you for the comment
Does a 1992 Ford Ranger 2.3 liter 5spd p/u have a fuel safety cut off switch?
I believe when pump is bad, however when its warm out (above 50°F) she starts right up. In winter (Baltimore Maryland area) it'll crank & crank & eventually catch & the truck will run fine all day after that. The other day while driving, hit a bump & she started to run like it's fuel starved.
Hello Paul. I'm curious how a ground wire could corrode and split when it's untouched and inside a plastic loom. It must have been chafing on a metal edge.
@scannerdanner. So it is not possible for long term fuel trim to read rich do to unburned fuel within cylinders?? Have u ever seen a gm waste spark system with a dead coil whith (no dtc )?? And on start up the thing ran smooth?? Well I witness this on a another 3.1.. I did not do a snap throttle
to load engine..my own ignorance. I just plugged scanner in to view fuel trim - 22 ltft .long story short first coil going left to right was dead, cylinder 2 and it's companion was not firing. On sta
The Analytical speed in which it took to find the common point 10 min, not Tom Cruise but diagnostically dude is Top Gun!!
Good find... I'll be looking for the same ou my car cause when the lights are on the engine at idle shakes a litle. And loose some power too...
love the
vid. but my question is if I've replaced the fuel pump and sending unit can the bad ground be in the wiring also
I think this has to be may favorite video from you and i have seen them all :) Keep up the good work!
My 87 ford ranger does not show the fuel level some people say it can just be a ground i also notice that whenever i try using my turn signals the front work well but the back ones both turn on at the same time regardless if i try to go just left or right both turn on. I have a misfire too can a bad ground cause also that?
wow man great how to. very knowledgable and i would have never tracked that bad ground down for those symptoms!
you rock man, ill def check out your other vids! keep on doin what you do man!
lol, me too when I played it back, but it was awesome wasn't it?
I got a 99 mustang gt the problem is it smells like old gasoline every time i start my when is cold and it has bad idle but when is hot it works fine can you help me you think is the fuel pump
As always amazing video with amazing diagnostic skills.Keep it coming Paul. Love it.
Thank you
Dan,I enjoy your videos, they are very informative. I am concerned with your technique of wire piercing.That should only be done in extreme circumstances,when there is absolutely no other way to obtain a measurement. And then the piercing needs to be weather sealed to prevent a future corrosion failure.Sorry for the criticism but, the fact that you are so adept at troubleshooting conveys the message that this is an acceptable practice when really it is the cause of A future problem. I hope you address this in the future. Thanks Bob
thank you my friend.
I have a feeling this is whats wrong with my 94' c1500 chevy 5.7. Its running great except for on the freeway after 65mph+ for 5 minutes it starts to slow itself down and Im having a voltage draw issue making my new alternator whine, removing the rear single plug wire makes the noise go away and back again when plugged back in. My blinkers are causing a huge voltage drop when headlights and brake lights are applied at the stoplight.
Sounds like two separate issues with one of them being a faulty alternator (lights dimming and whining)
@@ScannerDanner But its the 3rd new alternator ive put in in a week. NEW not rebuilt. I though they had bad bearings but its a voltage draw causing the whine and Im lost.
again, two separate issues, low power complaint with an alternator whine. Did these occur at the same time?
@@ScannerDanner 6 months ago I was on my way home from Lake Havasu on the 40 freeway. You have to have your headlights on when you leave Havasu on the 95 for daylight. I forgot to turn them back off after I got on the freeway and after an hour or so I started losing speed then truck died. Waited a few minuted then back on the road but it did it again within 5 minutes. Over and over until it finally quit, dead battery. Had it towed and the mechanic said he had to put a new battery cause old one wouldnt hold a charge, and that he had to put a fuel filter in to. Wouldnt turn over until the new battery then wouldnt start till the new filter was in, then it ran again. I drove it to Havasu one more time with no issues, but after I got back it started to do that to me on the freeway on my way home at night and has been doing it every single night for the last 3 months. Another new battery didnt help, and the origional alt started to go bad, the battery alt gauge was dropping as I was driving, replaced the alt and no more drop but the new alternator were whining. Old one wasnt. Unplugging the F(field) wire from the back of the alt make the whine stop, then returns when plugged back in. There must be a draw on that field wire. Im thinking there is a bad ground to my dash/ignition system, causing the fuel relay or pump to overhrat while on the freeway???? Last night I had to use my wipers and they were weird, running a few times then stopping for a second then running a few times and stopping again, slowed a bit then speed back up. When I turned on my headlights to leave work my sterio quickly cut out but was still working. Ground?????
Ive spent over $1500 over the last 2 months on mechanics/ diagnostics/ parts, Ive done research, asked around and cant get anywhere with this issue. Ive put in a new fuel pump, filter and injectors. A new Battery, throttle pos sensor, O2 sensor, ignition control module, MAP sensor, EGR valve and still have no joy. Last week I had the fuel pressure tested and the trans tested, both passed. No water in my oil or oil in my water. Fluids are all full and clean.
I had the same thing happen on a Toyota Camry 6 volts was dropping on the ground side of the fuel pump. But it would only happen when you applied the brakes.
I have a 1999 dodge ram it cuts off randomly and blinkers flash fast are the grounds hooked up the same like in this video?
Paul, that initial fuel pressure reading of 55 lbs.,is that a normal reading for these trucks? Being that Mitchell gives you a wide range of 30-65.
Do you know if they changed the way this was routed in the 2002 model? I'm working on a 2002 Ranger XLT. According to advanced autos scanner its throwing 33 codes! My cheap harbor freight meter grabbed 11. Everything from miss firing to transmission codes. When driving it dogs bad, like it's starting out in 3rd and never shifts, itll sit around 3 grand on the highway. I can manually shift it down to 2nd but not first. I'm guessing it's a 3 speed with overdrive.
I am not sure, sorry
I have a 2002 f150 4.2l. You definitely want to check maf.
This was not a MAF problem.
you are good I like the way you expres your self and tell oss the problem thanks all of you specialy you the one is talking
paul, just to make sure i understand, at 7:25 we see 4.62v. does that mean the pump is only running on 7.38v? when you turn the parking lights on we have a reading of 10.7v. so doesnt that mean that the parking lights, pump, and signals are running on 1.3v? the reason i ask is that at 7:35 you mention the pump is running at 4 volts. dont you mean 7.38v? i can very well be wrong.
Holy crap iv never seen that before Mighty job excellent video well done
Wow!!!!! God bless!! I can tell you were finally happy finding the problem. I have a problem with a crank but no start on my 2006 VIN#U Ford Ranger 3.0 V6. Can u give me any information that would help me?? Would the Ford Company be able to diagnose it if I tow it to them? Because one garage couldn't diagnose?? But it was a Tire shop where I had fuel pump put on. Willing to pay good money for information
Let's find you a shop in your area that is using SD Premium for training for their technicians.
Use this directory and if there isn't one close to you yet, there hopefully will be someday.
scannerdanner.com/find-sd-shops.html
I have a question for you if you wouldn't mind giving me some insight. (2001 ford ranger 3.0l -----15,000---- miles 2wd automatic return less fuel system fuel pressure is 68 koer koeo (extreme rich condition is the problem)) customer just put a new fuel pump in it because of bad check valve. problem existed before the new fuel pump, there was another pump put in it by the previous owner before the one yesterday, odd but this is the history I have on it. anyway the fuel trims are going lean 24% stft b1 and b2 ltft goes to about 6-8% negative b1 b2 before pcm kicks it out. if I create a huge vacuum leak like the booster line I can get the truck to start using trims. pcm fuel pump command is 100%? if I command the the pcm to have 40% duty cycle the pressure drops to about 37-40psi and the trims come back close to normal and the o2 sensors are reacting normally. the truck will negative trim the fuel until the pcm kicks it out and goes back to 0.0% trims across the board until reset. this truck ate 10 gallons of fuel in 80 miles please text me or call at 636-368-8267 or email at ghenke@hotmail.com. love your videos and have purchased your e book. there aren't too many cars I cant figure out but this one has really thrown me for a loop. thanks in advance Jerry Henke @ Alternative Auto Winfield MO
another comment is that the maf sensor and all other sensors are acting correctly considering the issue
Good vid. How did the wire get damaged like that?
Can something like this stop my fuel pump form activating ? Like when I go to start my ranger it just cranks but doesn’t start so I changed the fuel pump and made sure the inertia switch in an it still doesn’t turn on the pump please help
This one may help youth-cam.com/video/rQ7tvIxQSt0/w-d-xo.html
Ok, PVC contamination is very logical more then likely that is what happened.. I would have never thought about that.. I have a mental note of it now..
wiring problem ?
Hi Dan. Would you happen to know where the fuel pump ground wire terminates on a 2006 jeep liberty. Thank you
Not offhand, sorry
Oh and my name is Paul Danner, but that's okay, I get "Dan" a lot
Have a similar issue on '11 f150 6.2 v8. Trouble starting, left power running board not going down, driver seat not moving up or back, left tailgate lightbar all not working properly at intermittent times and not at the same time. Is there a place that isn't too expensive or free to get good wiring diagrams for my truck?
www.scannerdanner.com/forum/post-your-repair-questions-here/16-need-service-info-check-here.html
We've created a thread on my forum to help you guys with this. Thanks! It's free to join.
That was awesome investigative work. I would trust you with my vehicle👍👍👍👍👍
Sherlock Danner saves the day again.
@PDSVIDEO1966 Will do, thank you
Having similar issues low power n such thanks for your video it's something I haven't looked at yet thank you
Just curious how did you find the bad wire? Did you just probe around or did you use something else?
Great video Danner! I would like to see some real nightmare case studies like I get over here in the ghetto of south Kansas City! Lots of cars with backyard mechanics destroying things. Customers bring the cars to me with very little if any info about what the moron parts changer did!
@scannerdanner I have a 2000 Ford ranger 3.0 flex fuel with 101k miles on it
I have a intermittent code that's says p0176 flex fuel circuit can I can advice on the test or diag the issue without a o'scope?
+Xrio Sankara not sure off hand on that sensor. I think it is a frequency generating device. Post this question on my forum. I'm sure my guys over there can help you with some great details. www.scannerdanner.com
Thanks!
Was this bad ground wire under the drivers or passengers seat when looking up from underneath?
I have a 90 4S 10 left it running went into a store came out it was running no fuel no spark any suggestions all relays are good
94 s10
dan bleeck no spark on this system is usually either the pick-up coil in the distributor or the ignition module. I have a video on testing an ignition system with a test light that I will be unlocking in a day or so that will really help you. In the mean time watch this one. th-cam.com/video/mDKj19Hnhd0/w-d-xo.html
thank you it was the pick-up coil
oh right! i was using 12V as a baseline. dang. thanks again!
What about fuel trim values after repair? 😢
I've shown that a hundred times. Didn't think I needed to here as the fault was so unique
very interesting video more like this please.Thanks for taking the time and putting them on here.
@Hondatech26 thanks bro
hey great video dude , I have a f=different problem maybe you can answere , a 2007 ranger sport with a replaced motor of 61 k ,,,,,,,,,,,,, I was getting poor acceleration and hesitation . the scan read faulty bank 1 and 2 sensors , so I replaced them they were old and original and still have the same reading and hesitation . oddly , the temperature gauge gets to the middle id say operating temperature in less than 2 miles or so , can this be sending a bad or no signal to the computer to go from open to close loop ., it seems to do it cold also , in fla so not frezzing cold lol ,,,,,,,,,,,,,,,, I find it odd it would raise the needle to the middle so quickly is all , and can that sensor just be cleaned . or checked ? and would a open loop come up in an obd2 scan with the rich o2 sensor readings ?
As long as you get a code(check engine light), the vehicle will go into open loop by default.
You need to take your truck to someone who knows how to troubleshoot.
Oxygen sensor codes do not mean you need oxygen sensors. Sounds like a lean condition from your description.
You also need to make sure the correct engine was put in. Some of these are flex fuel systems that use different injectors than the regular gas only engines.
thank you very much!
Wow awesome video. Question should all fuel pump pressure be about 50 psi. I have a 04 jag 3.0 engine the x-type. The fuel psi is 27 is that ok. The car takes long to start sometimes.
They are all different. You have to look up a spec.
This is a bit of a shot in the dark, and not sure if you are able to offer us any advice, but we have a Ranger, 2002, XLT, 2.5TD, which is lacking in power generally. We have replaced the cylinder head and turbo, and renewed all the filters, etc, but although it runs without misfire, etc, it just has no 'oomph' to it? Any ideas????
Figured it out yet ?
Hello. I have a 98 mustang GT. It has a slight misfire in 2nd and 3rd between 1500-2500 RPM. My fuel pressure with key on, engine off is 0 PSI, 29 at idle. I replaced the fuel pump, filter and the regulator. I am going to pressure test the fuel pump but I have a feeling it was something to do with the electrical components or the injectors. Any advice on this one? Thank you.
This sounds like a light throttle misfire with is usually a secondary ignition symptom. While it is certainly NOT normal for fuel pressure to drop to 0 when you shut the car off, this may just be a leaking pump check valve which will have ZERO affect on how the pump performs when the car is running. The only thing this would give you is a longer than normal crank time.
There are other causes of fuel pressure dropping to zero on shut down that WILL cause some diveability problems (leaking injector, leaking psi reg diaphragm) but these will also cause fuel trim issues.
Do you have access to a scan tool that gives you your fuel trim numbers? If you do, I need hot engine idle STFT and LTFT on both banks and then 3000 rpm, again, both banks.
Hello. Thank you for your response. I just data logged everything. Where should I sent the Excel spreadsheet with the data? at hot idle, STFT on bank 1 was between -1.6 and +1.4 and LTFT started at -4.7 and climbed down to -6.2 with time. On B2 STFT was around -2.3 and LTFT started static at -3.9 and went down to -4.7.
At 3K RPM, on B1 , STFT was between -3.1 and -0.2 with occasional spikes up to +3.1. LTFT was static at -6.2. On B2 STFT was between -5.5 and -0.8. LTFT was initially -3.1 and then stabilized at -2.3.
Before the tests when I turned key one, engine off on a cold car, I had 0 PSI and 29 PSI with engine running. Interestingly, when I turned off the car, the fuel pressure was 29 PSI and the pressure decreased at about 10 PSI per 20 min. I have a return fuel system so I don’t know if this is acceptable.
During the second testing, on an already hot engine, I had 3 PSI with key on, engine off. Then repeated and the PSI jumped to 11 PSI and went I turned the key on the third time, it jumped to about 35 PSI. After I took out the key, the PSI dropped at about 2 PSI per 1.5 minutes. When I turned the car on with a hot engine, it again was 29 PSI. Gave it some snappy throttle and the PSI quickly went down to about 25-26 PSI and quickly came up to 29 PSI. With different loads at 1.5K, 2.5 RPM and 3k RPM, the pressure stayed at 28-29 PSI. Never went above 30 PSI. After I shut down the car, the pressure decreased by about 10 PSI in about 30 min.
Also, my scanner was stating that the fuel system was in closed loop all the time. From the first till the last second of data logging. I started logging with a completely cold engine and in the end after pressure testing, even went for a short drive with an operating temp. Still it was showing that it was in a closed loop. Is this normal?I would appreciate any advice. Sorry for any confusing sentences.
this data log isn't going to help me sorry, I would need to car
hey scanner danner i have a 2002 ford ranger has misfire on cyl 2 and ive replaced coil pack wires plugs and we replacing plugs i found cyl 2 was broken lol but its has rough idle poor mileage and dam thing is power loss from heck and we all know they are called 3.slows so its worse than normal its only got 136.xxx miles any help be appreciated im running outta ideaas lol
great vid, poer and grounds thaks paul 4 the time and knowlendges
Unbelievable work,excellent video & very well explained. You are one smart character.
Cheers ! from Victoria BC Canada -Les
Thank you Les!
You da man bro Great diagnosis I wish I was near you I'd take my truck for you to fix .....Where are you located
as pressure drops when the headlights being turned on "check out the fuel pressure, that's awesome." don't know why, but I giggled a little bit on the inside.
funny, i was thinking the exact same thing. hate to see Paul get run over trying to educate us.
My ford ranger xlt crunk bot not to start. The feuel injector sno presur.
are you saying there is no fuel pressure?
I got a 2000 Toyota Camry
P0304
P0171
P0500
I replaced
Cam Shaft Sensor
Crank Shaft Sensor
MAP Sensor
Cleaned the EGR
EGR Modulator
TPS
VSS - I am Still getting the P0500 (I have a multimeter so I will test that)
Radiator and thermostat
PCV valve and grommet
Timing Belt
Plugs and Wires
Used Lucas fuel injector cleaner X2 as well.
I have a new knock sensor but I could not get the new part on because that is EXTREMELY hard to get the old one off
The car will run for 15 miles then CUT OUT.
The car will restart 45 minutes later but misfire BADLY.
Something obviously is getting hot then killing the engine
Help Me!!!
I meet a guy at spare parts shop, he has a problem with his car when he start the air conditioner, the car shuts off. Maybe it is the same issue here. Bad ground,, possible.
If he can keep it running with his foot on the gas pedal, it is a different issue. I'd suggest a throttle body cleaning if that is the case
Crazy what a bad ground can do🎉
For sure!