I've seen a lot of these where they were extreme rich. When I see a low mass airflow value at idle, I go to the cat. But also there is the issue of the fuel pressure regulator. If the diaphragm blows, you get fuel pressure right through the vacuum hose into the intake. Extreme rich, lots of codes like maf low flow, very rich mixture, misfire codes and more.
Bro you are very intelligent.. Man to find a tech as knowledgeable about the field as you is amazing bro.. Thanks for the videos they are VERY INFORMATIONAL .. Ur the man keep it up 👍 (Coming from a Toyota Technican)
another great vid mr Danner, also note, everytime the engine stops you will hear a pop, this is the pressure in the exhaust making its way back through the intake. never seen a pressure guage spin around that far 0.0 i really enjoy your vids.
also some cheap oil pressure kits are including an M18x1.5 adaptor that can be easily used on the O2 sensor bung. Many thanks for the video , TOP job! (As we all know , apart from cat damage the overfueling condition may also lead to oil dilution and bore wash. I had this scenario on a GPL converted petrol engine, and GPL wrong setup damaged the O2 and when using gas a full false lean condition was reported by the sensor )
Hey Paul Thank you for the video . Im suspecting this might be my issue I just replaced the Fuel pump on my Town and Country after it being tested and Tech said amps were bad due to being worn out and getting hot . I do believe a lean condition causes the engine to run hotter . So i could have a partially melted Cat Causing a Lean condition and also had a Old Fuel pump that was getting hot with or with out the Cat and possible 02 issue . Will find out more on Fri at its next appointment . Could you please make a post about how your Mom is doing ? My Fave Video is everybody at your Bros Shop :) Take care
Been watching your Ch.4 and 5 playlist lately! and It's very well done! I'm learning so much! I must say there is one type of video missing that I wish you had, and no one else on TH-cam that I've seen has one yet! Vehicles with those 5 wire wideband upstream o2 sensors! I'm working on a buddy's car right now for a bad upstream o2 and it's the first 5 wire I'm troubleshooting. I see how it forms an arc on the data screen when you start the engine, and the voltage will vary up and down (instead of oscillating) to maintain the perfect air/fuel ratio. But I'm not too sure how to tell if one of those 5 wire o2s is bad. In the case of my buddy's car, the upstream wideband o2 contradicts the downstream. Upstream shows lean while downstream shows rich. I performed simulated mixture tests and downstream reacted accordingly while the upstream did not react at all, nor did fuel trims change. I know this would indicate a bad upstream o2, but this wideband seems like it works every time you first start the car (cold or hot), and then fixes lean after about a minute of run time and then does nothing. Is it possible to have a wideband o2 work intermittently at first and then have an open circuit after about a minute? Granting there's no exhaust leaks, vacuum leaks or anything like that? The three codes I'm dealing with on my buddy's car (2009 Kia Spectra 2.0l) are: P2626: Pumping Current Trim Circuit Open; (upstream o2) P0171: System too Lean; P2097: Post Catalyst Fuel Trim System too Rich. I hope someday you're able to work on one of these 5 wire o2s and film it! I gatta say I like conventional o2's better, as far as troubleshooting them lol! Thanks for reading and thanks again for all your hard work and awesome videos!
I don't have the 5 or 7 wire widebands but I do have some wideband case studies. One from my brother too that I recommend and go over with my class. It should be listed in one of those two chapters playlist. Thank you!
Great Video Paul. Probably wouldn't do this in the field, but if I wasn't under a time constraint, would probably put a test pipe in place of the catalyst, replace the sensor, and then make sure the engine is running correctly and block learn and integrator look good before installing the replacement cat. That way if you have another issue such as a weak ignition or fueling issues with injectors, you'll catch it before calling the customer for a final estimate. That would also tell you if you have something stuck down stream since you have no post cat sensor bung to screw into.
Paul,another great video! Thanks for the effort of showing the steps in diagnostic even though it's so difficult with the car not running. Is it safe to say that this O2 has been lying for a long time and because of all that extra fuel being dumped in the exhaust and making that cat run at a abnormally high temperature led to the eventual failure of the converter?
I would say yes, but there also could be another issue unknown until the cat. gets replaced. Hard to troubleshoot any other engine running problems when the engine cannot breathe
I apologize,I was eager to ask the question and didn't wait for the end of the video,when in fact you do say the the fixed lean O2 caused the cat to melt.
Great suggestion my friend. I could have done that, just chose to go at the O2 due to its easy accessibility and the fact that I had to remove it anyway.
i hope you explain step by step how to use graph for o2 sensor and what is short term and long term . i have scanner matco maximus 2.0 and i am trying to figure out how to use it correctly
Thanks Paul! Where can I find out what the PIDs are for and there correct readings? I did a 2012 F150 and it had PIDs on it I never seen before and was concerned that not knowing what they were might be related to the problem I was having I know that some of the readings will vary depending where your at
great video paul i noticed you selected the pids you wanted to see sort of a custom data list didnt know that could be done on an OBD 1 car. is that because of the scan tool software? also paul is the refresh rate that much faster because you are not looking at every pid ? thankyou paul mark ferraro
Paul, I have an old tbi chevy. (94'). There aren't many videos with useful info on the older systems. Would you have time to do some diagnoses? I'll pay for your time.
Interesting it would run at all even when cold with that much pressure to peg the gauge. I don't want to be a "naysayer", but you could use a vacuum gauge on the intake, especially for those that don't have a back pressure gauge. Maybe a option on a vehicle that has a hard to access up stream O2/AF sensors. A back pressure gauge is on my to buy list though.
Yes. I agree with roastlambpie. First of all, I would use a vacuum gauge on the intake. Let the engine stop for a while and connect the vacuum gauge. If the engine is able to run, watch the vacuum gauge and hold the rpm to 2500, You will be able to see the reading is slowly dropping with restricted exhaust. Of cause, if you want to make sure you can carry out another test. But I still like the way Paul shows us.
ScannerDanner I agree vaccum test is good some times but back pressure gauge leaves not question, one example will be if MAF sensor is not working properly when you snap you loose all vacuum and is not plugged exhaust.
I'm having problems with a 1999 golf gti vr6 I've checked the thermo switch coneccted it to a direct power source and they work and I've check the relay switch not sure what to do next help please
I have a 98 dodge ram 1500 with 5.2. Pulls a po171 code lean bank one slow response. I have replaced every sensor , vacuum leaks,idle control valve, catalytic converter, gasket under throttle body. Mas sensor. Can undo battery put back on truck runs great for fifty miles engine light comes on idles up and down, gets 5 mpg and reads lean bank one code. There's nothing else to replace that I know of. Help. Short term fuel reads 32.5 long term 0.0.
ScannerDanner Is this an OBD1 Vehicle?, Those Codes and Pids look totally different to what you normally show on the scan Tool during your videos on the more modern vehciles.... OBDII was manadatory in 1995 onwards correct? i know some cars like some nissans were OBD2 Before that time though, like 1994 Maximas.
1996 and up are OBDII. Some 94 and 95 model years had 16 pin OBDII data link connectors but were not fully OBDII compliant until 96. Also technically speaking the only true OBDI vehicles were California emissions. This would be a pre-OBDII system (not OBDI, not OBDII). Before 96 and outside California, the manufacturer had more freedom to do what they wanted.
ScannerDanner Thanks, Thats clears it up a bit. Though By Pre-OBDII you mean its somewhere in between OBD1 and OBDII and supports *SOME* OBDII functions (hence why the Verus can talk to it?) but not all, but also has Manufacturer specific functions as well? Our 1995 (and i meant 1995 above lol) Nissan Maxima (A32 Series) is Supposed to be OBD2 atleast partially and is meant to have a DLC connector in one of the front footwells, But i cant find the dam thing, Yet all those on the maxima forums say its there (however they are american and im Australian, that might explain it), and the Service manual with all the harness diagrams also states it there, however the manual for is a Left hand drive, but being in AU our cars are right hand drive.
KSSilenceAU Any car built before 96 that is NOT California emissions is pre-OBDII. Just like OBD II, OBD I (California emissions) had mandates by the government For example, take a 1992 Nissan Pickup truck OBD1 (California) version had a check engine lightPre-OBDII (every other state) there was no check engine light!So you see one of the requirements of OBDI was there had to be a check engine light to warn the driver. It really is just picking on terms, call it OBD I if you want, everyone will know what you mean. Many manufactures offered data and bi-directional controls all the way back to 1984! While others offered nothing but an LED light on the computer board for trouble codes.
hi SD got a wierd issue with my e46 318 m43 engine i keep having code come up 'breaking down process low' would that be the cat ? front lambda fluctuates from .08v-0.8v and rear stays at steady 0.45v from what i have read that is normal but my mot (in the uk) had a lambda reading of 1.29 on the gas test which is lean but the live data shows 1.01. exhaust doesnt have a leak so i clear the code but it comes back up after driving a bit with the same code. i know its a long shot of you replying but i thought id still try.
Hello sir , can you help me ? so the problem is 1.6 opel zafira CNG LOW POWER > STFT.B1 S/2 >0.99.2 % STFT B1 S/1 >0.0 % STFT B1 0.0 % STFT B1 -3.9% O2 B1 S2 0.845 v O2 B1 S1 0.285 v thank you very much yonan
The needle turns like 720 degrees! WTF? ROLF! I thought that it going to take off!!! Oh my God! Doesn't the owner get a check engine light when the O2 fails probably a lot of time before the catalytic converter?
Excessive fuel, as in a stuck open injector, would flood the cat with fuel and put the flame out, so you're right, it won't hurt it. But that is the only scenario. Every other incomplete burn, or rich, or lean condition can and will overheat and melt the cat
I'm having problems with a 1999 golf gti vr6 I've checked the thermo switch coneccted it to a direct power source and they work and I've check the relay switch not sure what to do next help please
![MAF and Wideband O2 Sensor Testing for a P0172 [Rich Condition]](http://i.ytimg.com/vi/_z6HoW4OiD8/mqdefault.jpg)
![MAF and Wideband O2 Sensor Testing for a P0172 [Rich Condition]](/img/tr.png)
I've seen a lot of these where they were extreme rich. When I see a low mass airflow value at idle, I go to the cat. But also there is the issue of the fuel pressure regulator. If the diaphragm blows, you get fuel pressure right through the vacuum hose into the intake. Extreme rich, lots of codes like maf low flow, very rich mixture, misfire codes and more.
Bro you are very intelligent.. Man to find a tech as knowledgeable about the field as you is amazing bro.. Thanks for the videos they are VERY INFORMATIONAL .. Ur the man keep it up 👍 (Coming from a Toyota Technican)
another great vid mr Danner, also note, everytime the engine stops you will hear a pop, this is the pressure in the exhaust making its way back through the intake.
never seen a pressure guage spin around that far 0.0 i really enjoy your vids.
This channel is a gold mine. Thank you. I am experiencing exact same symptoms on 2003 Ford escape 3.0
also some cheap oil pressure kits are including an M18x1.5 adaptor that can be easily used on the O2 sensor bung. Many thanks for the video , TOP job!
(As we all know , apart from cat damage the overfueling condition may also lead to oil dilution and bore wash. I had this scenario on a GPL converted petrol engine, and GPL wrong setup damaged the O2 and when using gas a full false lean condition was reported by the sensor )
Hey Paul
Thank you for the video .
Im suspecting this might be my issue
I just replaced the Fuel pump on my Town and Country after it being tested and Tech said amps were bad due to being worn out and getting hot .
I do believe a lean condition causes the engine to run hotter .
So i could have a partially melted Cat
Causing a Lean condition and also had a Old Fuel pump that was getting hot with or with out the Cat and possible 02 issue .
Will find out more on Fri at its next appointment .
Could you please make a post about how your Mom is doing ?
My Fave Video is everybody at your Bros Shop
:)
Take care
Been watching your Ch.4 and 5 playlist lately! and It's very well done! I'm learning so much! I must say there is one type of video missing that I wish you had, and no one else on TH-cam that I've seen has one yet! Vehicles with those 5 wire wideband upstream o2 sensors! I'm working on a buddy's car right now for a bad upstream o2 and it's the first 5 wire I'm troubleshooting. I see how it forms an arc on the data screen when you start the engine, and the voltage will vary up and down (instead of oscillating) to maintain the perfect air/fuel ratio. But I'm not too sure how to tell if one of those 5 wire o2s is bad. In the case of my buddy's car, the upstream wideband o2 contradicts the downstream. Upstream shows lean while downstream shows rich. I performed simulated mixture tests and downstream reacted accordingly while the upstream did not react at all, nor did fuel trims change. I know this would indicate a bad upstream o2, but this wideband seems like it works every time you first start the car (cold or hot), and then fixes lean after about a minute of run time and then does nothing. Is it possible to have a wideband o2 work intermittently at first and then have an open circuit after about a minute? Granting there's no exhaust leaks, vacuum leaks or anything like that? The three codes I'm dealing with on my buddy's car (2009 Kia Spectra 2.0l) are:
P2626: Pumping Current Trim Circuit Open; (upstream o2)
P0171: System too Lean;
P2097: Post Catalyst Fuel Trim System too Rich.
I hope someday you're able to work on one of these 5 wire o2s and film it! I gatta say I like conventional o2's better, as far as troubleshooting them lol! Thanks for reading and thanks again for all your hard work and awesome videos!
I don't have the 5 or 7 wire widebands but I do have some wideband case studies. One from my brother too that I recommend and go over with my class. It should be listed in one of those two chapters playlist. Thank you!
@@ScannerDanner I will look for it!!! Thank you so much for responding! I know you're a busy man! Much appreciated Mr. Danner!
Comment on those videos too, I do my best to respond to everyone of them.
You can also have a interment restricted exhaust from a melted CAT, seen the substrate turn into a ball and rotate inside of the CAT. pretty cool
Great Video Paul. Probably wouldn't do this in the field, but if I wasn't under a time constraint, would probably put a test pipe in place of the catalyst, replace the sensor, and then make sure the engine is running correctly and block learn and integrator look good before installing the replacement cat. That way if you have another issue such as a weak ignition or fueling issues with injectors, you'll catch it before calling the customer for a final estimate. That would also tell you if you have something stuck down stream since you have no post cat sensor bung to screw into.
Excellent advice, to look for debris downstream of the cat.
I just wanted to say that I did see the black smoke coming out of the tail pipe if that helps.
Excellent tip on the Back pressure
Great job Paul, awesome troubleshooting!!
Keep up the good work.
Paul,another great video! Thanks for the effort of showing the steps in diagnostic even though it's so difficult with the car not running. Is it safe to say that this O2 has been lying for a long time and because of all that extra fuel being dumped in the exhaust and making that cat run at a abnormally high temperature led to the eventual failure of the converter?
I would say yes, but there also could be another issue unknown until the cat. gets replaced. Hard to troubleshoot any other engine running problems when the engine cannot breathe
Paul, Hi you can use an old ford spark plug (18mm) to make an adapter for a back pressure test.
I apologize,I was eager to ask the question and didn't wait for the end of the video,when in fact you do say the the fixed lean O2 caused the cat to melt.
Excellent video as always. Great tip. Regards,
Another great video thanks for sharing Paul.
Great video.
Wouldn't using the EGR sampling tube for your vacuum/pressure gauge work testing exhaust back pressure?
Any reason for not taking a running compression wave ? The exhaust plateau would have given you the answer.
Great suggestion my friend. I could have done that, just chose to go at the O2 due to its easy accessibility and the fact that I had to remove it anyway.
i hope you explain step by step how to use graph for o2 sensor and what is short term and long term . i have scanner matco maximus 2.0 and i am trying to figure out how to use it correctly
th-cam.com/video/oRX2V6_a3dc/w-d-xo.html
with a suspected clogged cat u can remove the upstream 02 to keep the vehicle running and to help diagnose clog.
yes and also use the Bunghole to check the back pressure..
excellent video paul
Man I want to come to where you teach brother! You know your shit!
No kidding, wish there were mechanics like him in my area.
My favorite is the in cylinder pressure transducer
Very good testing .
Thanks Paul! Where can I find out what the PIDs are for and there correct readings? I did a 2012 F150 and it had PIDs on it I never seen before and was concerned that not knowing what they were might be related to the problem I was having
I know that some of the readings will vary depending where your at
One place would be the troubleshooter of snap on scan tools, under fast track data scan
thanks Paul Danner
Thanks for sharing you videos.
I thought you had the answer from the codes.Why did this all happen? Quad driver,shorted injector or pcm problem?
great video paul i noticed you selected the pids you wanted to see sort of a custom data list didnt know that could be done on an OBD 1 car. is that because of the scan tool software? also paul is the refresh rate that much faster because you are not looking at every pid ? thankyou paul mark ferraro
refresh rate is so much faster when PIDs are limited. It is a standard practice for sure.
Thanks Mark!
Hey Paul that is a nice looking exhaust pressure gauge where did you find that baby? Mark ferraro
Paul, I have an old tbi chevy. (94'). There aren't many videos with useful info on the older systems. Would you have time to do some diagnoses? I'll pay for your time.
No, I do not, sorry. If you are in the Pittsburgh PA area, take it to my brothers shop. He is in Bethel Park PA (Danners Automotive)
@@ScannerDanner cool. Thought he was in ohio.
If the engine would run would the down stream sensor read similar to the up stream because of the condition
There is no downstream O2 on this system. Too old
If there was one, it would be reading full rich as the front O2 was lying to the computer.
Thanks!
Interesting it would run at all even when cold with that much pressure to peg the gauge.
I don't want to be a "naysayer", but you could use a vacuum gauge on the intake, especially for those that don't have a back pressure gauge.
Maybe a option on a vehicle that has a hard to access up stream O2/AF sensors.
A back pressure gauge is on my to buy list though.
Yes. I agree with roastlambpie.
First of all, I would use a vacuum gauge on the intake. Let the engine stop for a while and connect the vacuum gauge. If the engine is able to run, watch the vacuum gauge and hold the rpm to 2500, You will be able to see the reading is slowly dropping with restricted exhaust. Of cause, if you want to make sure you can carry out another test.
But I still like the way Paul shows us.
I do not like any test that the final result has variables. The vacuum test result has variables and I've seen plugged exhausts pass the vacuum test.
ScannerDanner even at full throttle snaps? it should be very pronounced on the vacuum gauge.
ScannerDanner
I agree vaccum test is good some times but back pressure gauge leaves not question, one example will be if MAF sensor is not working properly when you snap you loose all vacuum and is not plugged exhaust.
Joel N Can you elaborate how a bad MAF can change engine vacuum?
I'm having problems with a 1999 golf gti vr6 I've checked the thermo switch coneccted it to a direct power source and they work and I've check the relay switch not sure what to do next help please
I have a 98 dodge ram 1500 with 5.2. Pulls a po171 code lean bank one slow response. I have replaced every sensor , vacuum leaks,idle control valve, catalytic converter, gasket under throttle body. Mas sensor. Can undo battery put back on truck runs great for fifty miles engine light comes on idles up and down, gets 5 mpg and reads lean bank one code. There's nothing else to replace that I know of. Help. Short term fuel reads 32.5 long term 0.0.
Did u resolve with car? Did u try to unplug o2, then maf/map?
ScannerDanner Is this an OBD1 Vehicle?, Those Codes and Pids look totally different to what you normally show on the scan Tool during your videos on the more modern vehciles.... OBDII was manadatory in 1995 onwards correct? i know some cars like some nissans were OBD2 Before that time though, like 1994 Maximas.
1996 and up are OBDII. Some 94 and 95 model years had 16 pin OBDII data link connectors but were not fully OBDII compliant until 96.
Also technically speaking the only true OBDI vehicles were California emissions. This would be a pre-OBDII system (not OBDI, not OBDII). Before 96 and outside California, the manufacturer had more freedom to do what they wanted.
ScannerDanner Thanks, Thats clears it up a bit. Though By Pre-OBDII you mean its somewhere in between OBD1 and OBDII and supports *SOME* OBDII functions (hence why the Verus can talk to it?) but not all, but also has Manufacturer specific functions as well?
Our 1995 (and i meant 1995 above lol) Nissan Maxima (A32 Series) is Supposed to be OBD2 atleast partially and is meant to have a DLC connector in one of the front footwells, But i cant find the dam thing, Yet all those on the maxima forums say its there (however they are american and im Australian, that might explain it), and the Service manual with all the harness diagrams also states it there, however the manual for is a Left hand drive, but being in AU our cars are right hand drive.
KSSilenceAU Any car built before 96 that is NOT California emissions is pre-OBDII. Just like OBD II, OBD I (California emissions) had mandates by the government For example, take a 1992 Nissan Pickup truck OBD1 (California) version had a check engine lightPre-OBDII (every other state) there was no check engine light!So you see one of the requirements of OBDI was there had to be a check engine light to warn the driver. It really is just picking on terms, call it OBD I if you want, everyone will know what you mean. Many manufactures offered data and bi-directional controls all the way back to 1984! While others offered nothing but an LED light on the computer board for trouble codes.
The tps is stuck at .40. Mine jumps rapidly from 0 to .4. is that normal
Great Video....Thanks
hi SD got a wierd issue with my e46 318 m43 engine i keep having code come up 'breaking down process low' would that be the cat ? front lambda fluctuates from .08v-0.8v and rear stays at steady 0.45v from what i have read that is normal but my mot (in the uk) had a lambda reading of 1.29 on the gas test which is lean but the live data shows 1.01. exhaust doesnt have a leak so i clear the code but it comes back up after driving a bit with the same code. i know its a long shot of you replying but i thought id still try.
Very goodntesting
What book are you referring too??
My book! It is available from my website at www.scannerdanner.com
I offer a 100% money back on the eBook if you want to check it out.
Great video
Hello sir , can you help me ? so the problem is 1.6 opel zafira CNG LOW POWER >
STFT.B1 S/2 >0.99.2 %
STFT B1 S/1 >0.0 %
STFT B1 0.0 %
STFT B1 -3.9%
O2 B1 S2 0.845 v
O2 B1 S1 0.285 v
thank you very much
yonan
My Mentor Sir ScannerDanner
👍
PROFICIENT Sir ScannerDanner
From Nick Ayivor from London England UK 🇬🇧 ⏰️ 22:12pm
no shops near me are like this. All weekend warrirs just taking peoples money and doing half-assed worok. Many of us just learn and do our own.
hi paul were csan i buy youre book?
www.scannerdanner.com
Thanks!
awesome!
awesome, I think that gauge is pressure gauge.
i hope they changed the oil too
sorry posted before finished vid.
The needle turns like 720 degrees! WTF? ROLF!
I thought that it going to take off!!! Oh my God!
Doesn't the owner get a check engine light when the O2 fails probably a lot of time before the catalytic converter?
P0421 on a 2006 mazda 3 Canadá emission car. There appears to be two cats with a resonator, two o2's and another "o2" reading milli amps....any help?
I know it does, but why does fuel kill a cat? I would think excess fuel would not melt it but make it cooler.🤔
Excessive fuel, as in a stuck open injector, would flood the cat with fuel and put the flame out, so you're right, it won't hurt it. But that is the only scenario. Every other incomplete burn, or rich, or lean condition can and will overheat and melt the cat
Look for the banana
ok i dont even know what a quad driver module is
Just a fancy name for 4 different output drivers monitored by some stupid ass name lol
fucking awsom
your lucky that thing hasnt blown all of its gaskets.
this guy is the shyt..
I'm having problems with a 1999 golf gti vr6 I've checked the thermo switch coneccted it to a direct power source and they work and I've check the relay switch not sure what to do next help please