Very well explained. Thank you. Found code for IAC on a vehicle that i was working on today. Engine is really rough. Multiple misfires, running rich and whatnot. Perfect time to perform test.
This is a great video. I've been working on an idle issue on my mercruiser boat engine. Someone explained to e that I should check for power and resistance on my wiring harness at the IAC. I had no idea how to do that until I watched your video. Great attention to detail. The inset camera view as you test for resistance is a great feature! Thanks a bunch!
What are the part#'s for the 5 screws that hold the IACV to the Throttle Body? I messed up those phillips head screws removing them cuz they were a bit stuck. 2001 Maxima GLE
Thank you for showing the way to test the IAC. I am going to test mine tomorrow. I was really worried that I was going to have to replace the part and I don't have a lot of cash. SUBSCRIBED!! And please keep the videos coming this one was very informative.
Would be the same test for a two pin set up. 2001 ford ranger 3.0l I put in a new one and still getting the code and running really bad. I''m thinking it might be a bad ECU. Any thoughts
Great explanation... I followed your last test. When I turn on the ignition I hear the IAC click and if I leave it in the ON position for a few secs without starting the engine, the IAC clicks back to the off position. Is this normal behavior? Thanks Jake
Thank you for the video. Quick question, I was getting P0505 too and bought a replacement part on Amazon. No more p0505 code but this particular IAC makes noise when the key is set to accessories. It sounds like a little motor is constantly running. Is that normal or should I ask for a replacement?
Do I need to reset my computer on my 1999 Subaru legacy outback, after I check and clean my IACV? I didn't actually remove it all the way but after reassembling, my car is now acting like my battery isn't working for a minute. It starts but immediately dies. When I try to turn over again, it acts like I have a dead battery but if I wait a second then try again, it starts but not in a strong way. I know my battery is fine because I just got it tested. When my father and I replaced and adjusted my TPS the other day, we followed the recommended computer reset protocol and that got rid of the At Oil Temp and check engine light. It is shifting so smoothly now and all seemed perfect so we decided to see if we could clean the IACV, we were concerned we might screw it up so just shot carb cleaner into it and then put all the hoses and sensors back into place. Seemed to be fine until the next day when I went to start it and experienced it dying and then having issues starting. I've never had an issue with it starting. Wondering if i should've done the computer reset after messing with the IACV too. Or perhaps we didn't put something back correctly? Anyone have any advice here?
Thank you! Looking at a car with no real issues except an IAC code. Your video has LOTS of testing info, and the picture-in-picture was a NICE addition. Very informative!
All your testing checked out for me except for the last step at 5:20 on my 95' 3000GT. When I turned the car on several times, the shaft did not move at all. I decided to try it again and the first time I turned it on, it moved ever so slightly but wouldn't move again after I turn it back off and on. Is this an indication this part needs replacing?
Does this work for motorcycles as well? I’ve took my IAC valve of and left it connected..when I turn the key to on position, it doesn’t move at all.. Side note: I’ve been having problems with my motorcycle not being able to idle for more than 5 seconds..I changed everything but today I decided to check the IAC valve and it doesn’t move on the key on position
Question regarding a 2002 Nissan Sentra GXE. The resistance check is good and the voltages are good. I have removed the valve to check if it moves when turning the ignition on/off and it does not move. The valve was taken off of a working car. Any suggestions?
Great video, but I need to go a bit deeper. I want to learn exactly how the IAC steps, they are not simply fully open or fully closed, they can be set to various positions by the ECM to get different idle speeds. Yours has two sets of 3 pins. Pins 2 and 5 have 12V to them, then I guess a Ground signal from the ECM on pin 1 half steps the valve in one direction and then a Ground on pin 4 puts the other half step in that direction. To move the valve the other way, the ECM applies Ground signals on the 3 an 6 pins in a similar fashion. Is that correct? I have a GM 1987 2.8L V6 Fiero. My IAC valve has only 4 pins. I want to make a setup to actuate the value on the bench. My brother is an instructor at Porter and Chester and he would like to have a little set up to demonstrate how IAC valves work to his students. So learning how they actually work is the first step. I read 50 Ohms across each pair. I guess one pair moves the valve in one direction, and the other pair moves it in the other direction - but not quite, read on. I took some baby steps and tried it with 5V first... no action. Then I tried it with 9V (to be safe). One pair of contacts, still no action, but on the other pair puts a small twitch on the plunger in one direction (even if I reverse voltage polarity on the pair, it still twitches in the SAME direction). Ok, I guess it does use 12V, but seeing just a twitch is on right path. But the twitch was rotational on the plunger NOT in or out, and again, I expected it to twitch in the other direction using the other pair of contacts - but not the slightest twitch with those contacts! So, before I try it at 12V, I need to get a better idea on what signals/timing the ECM puts on the IAC valve to actuate it. There appears to be no position feedback from the valve to the ECM. I guess on power up, the ECM steps the valve many, many times to get to a fully open (home) position, and then the ECM keeps track of the step pulses to determine its position from then on - until power off. I have used stepper motors many times in the past, and that is what is nice about them, you don't normally need any feedback because the are dead on accurate on the position (and knowing it's position) if you pulse them properly. But I have no operational specs on my IAC valve. Any ideas? Thanks.
Ok last question...? I took off the IAC itself, and there is a little coolant on it and inside the housing. Is that ok as coolant runs through part of it, or should it be completely dry?
And when i pulled the TB off, I found all sorts of coolant basically caked in there. I cleaned what I could and shot a lot of Seafoam inside to hopefully loosen more.
Does the first test applicable in all 6 pin iacv? Mine is suzuki and has a 6 pin iacv. I wanted to test the iacv coz my engine when running for 30 mins there's a problem occure like when you press the accelerator a little bit the rpm will surge to 1800. Also I notice that when the ac compressor cut off the rpm also surge to almost 1800.
hey just saw this awesome vid. but I came into a problem. did everything you did and everything thing checked out cleaned it up a bit then put it back in but still have code showing. any advice?
I tested the IAC VALVE like you did in the end of video. And it only move left to right not out and in. Does it need replaced? Can I send you a video of what it does so you can see what it does thanks.
Hey man i have a question. I did the last test and the pintle shot out of the IAC. Is that because i was stupid or something else every time i turned the car to the off position it would go out so far then it shot out still trying to find it as we speak.
I have a 04 Ford Freestar that will act like it's running out of gas at first cold start. Fuel pressure is fine. If I hold RPM's at 3000 or more for a minute it will be fine but RPM's at idle are jerky. No check engine lights are on. Sound like the IACV to you? Thanks
your very detail about your videos there great.. i was hoping you could help me out. i had a stuck idle pulley it was melying the blet. change it works good now. but i noticed that my 2003 dodge durango truns off now when im at stop. also if i have it on park and give it some gas about 4,000 rpm it dies... i was told to adjust idle. would you know how yo do that.. i was also told that i should just clean the throttle body and iac.. any recommendations.. thanks
Great video. Buying a good digital meter paid off with its first use. Since my Eclipse GT wasn't throwing any codes, but wouldn't idle, I needed to test the part I thought might be the culprit. This video showed me how to do it. New IAC= Big smile & big savings!
Good good video, T have a 01' Mazda Tribute 3.0. Idles rough, checked IACV clean inside. No power at key ON! Im on disabillity, things are tight like most places. That fuse on the IACV also tends to EEC, VPWR, EVR, MAF, ( bulkhead)? Most abbreviations I'm familiar, but EEC , EVR? V power ! I guess ? Ha ha it starts right up! 5 seconds later it starts to stumble to death (dies)! Plz sir i need help .
Great video, you test for power in the sensor, the sensor has 6 pins, you only showed the two for power, what are the others 4 pins that you did not test, are they 2 grounds and two signals? Please let us know and what are the voltage of those others pins, thank you. Cheers from ontario ca
So this must be the winding noise I hear...I just installed a repaired ecu from ebay and my car won't stay on unless I give it gas once it warms up it will stay on...where can I get a new one iac and why is the ecu not calibrated to work right
@ carsntoys - I have a 1998 Ford Explorer XLT that idles poorly when cold & only a little better when warm. Is the IAC the problem, or O2, or F/A sensor or "all of the above" ? No Hate On's Please.
+CarsNToys - It was the O2 sensor 1, bank 1. I replaced it (with much grief), with a new one & seems to idle ok. I then took the negative battery cable off for 5 mins., but the check engine light is still on, but the system says all is ok.
Could you please help me locate the IAC location on 2002-2005 Audi A4 1.8T B6 Model? mine is 2005 B6 and I am having terrible time with my idling. Every effort to locate the IAC has been unsuccessful
Question: I have an IACV that's got only 4, not 6, terminals. So I did the ohms test on 1 + 2, 2+ 3 and 3 + 4. 1 + 2 and 3 + 4 showed about 53 ohms, but 2 + 3, nothing. Does that suggest a fault? Thanks.
i replaced the iacv with a used one and still the same problem, at cold starts it stalls until it warms up, no vacuum leaks. what else could it be or should i have replaced it with a nee iacv? thx.
Can you show how to check harness for short to ground and short to power? This is actually the next step someone should do after doing the methods you showed. Thanks.
Great videos. I have a P0505 hard code which I believe has something to do with either the ISC motor and/or ECM. But before I fix this code and spend lots of money, I noticed that all four of my readiness monitors are NOT complete. I understand the procedure to reset these readiness monitors, but do I need to repair this P0505 first BEFORE I can run the readiness monitors? Is there another option or procedure to reset these readiness monitors first? I know I can get several other codes when the four readiness monitors are run, but is there a way to reset these monitors so I have an idea of what else is wrong with my vehicle? I don't want to spend money to repair code P0505 ONLY to find out other codes later when the readiness monitors are run. Please help.
Hi David, in my car, the coil part is easier to remove than the entire IAC. I did a test, the harness was getting 11v, some pins on iacv was having 30ohms while some had 29ohms. While car was idling(though rough idling), I unplugged the iacv harness, i didnt notice any change. If I change only the coil, will the effect be same as changing the entire iacv?
how you're doing I have a 1996 mercury grand marquis gs and it's making a very loud humming noise and I thought it was a wheel bearing but it wasn't a wheel bearing they said it was a idle air control valve so all I have to do is just change it and it will eliminate the problem
I'm getting the code to suggest mu iacv us bad. When changing out the iacv am I required to install a new ecm? I've read in several place I should, but your vedio didn't suggest it. Btw, I talk your video as gospel as you do amazing work. One last thing I have a 97 infiniti i30 if that matters. Thanks.
+Bobby Gee Did you get this fixed? You need to check the ECM if its bad also. When the IAC goes bad, it shorts out the chip in the ECM (this is a common occurrence in maximas and i30s). You'll see a burned chip if you take out the ECM. GL
Good Video work with the Picture In Picture (PIP) showing the details of the testing the connectors. Those details make all the difference when trying to learn what you're doing. The are a lot of instructional videos on TH-cam but the camera work is so bad that your not able to see what exactly that the person is working on. I appreciate the extra attention to detail for learning purposes. Keep up the good work
I have the code and replaced the iac # 530 306 57ab on a 1999 dodge Durango. After spraying carburetor cleaner all over the carb and cleaning it and putting on the new iac it will not start at all. The security light is on. I disconnected the battery to reset it still won't start.
I tested the prongs on my Idle Air Control Valve and they read 42 to 46 Ohms on each compared to your 30. Same model of car (Nissan A32). Is that something to be concerned about? Also, when removed but connected to the harness, it moves, but not as much as in this video. It's possible that's just a subjective observation, but if it really doesn't move as much, that a cause for concern?
+Antonio Java The 30 ohms reading can vary depending on temperature. And if the valve is moving back and forth, and you don't have a trouble code for p0505, I wouldn't worry about it.
+CarsNToys Thanks, man! :) This helped me a lot in troubleshooting my car problem. I actually don't have a code scanner, so I had to do things the old-fashioned way and checked every possible point of failure one by one, including this part (which turned out to be fine, based on your input :) ).
my car idles like crazy and stops on me its a 96 nissan maxima if i clean ghe iac will it help i cleaned first half of my throttle but didnt take it fully apart to clean.other side any tips? i really need to fix this
I have done all does test and i get 30 ohms and 12v on the harness and i still get the p0505. I even bought a new IAC but no luck. I also tested the continuity from the harness to the ecm and it was good. What can it be?
James Jimmy The only thing I can recommend is see if you can get your hands on the factory repair manual. Maybe there's something else to look at on your Mitsubishi. Out of curiosity, any other trouble codes?
I checked mine it does shows everything you've had explained but still have the problem.& the scan shows a bad iac what it could be i already cleaned the EGR as well but i don't see any changes. Any suggestions???
Gotcha. On your vehicle try doing an ohms test on the valve. Grab a digital multi-meter and see if you're getting resistance. Here's another video showing how to perform an ohms test. Fast forward to 50 seconds: th-cam.com/video/j-Wr2VMvfbc/w-d-xo.html
does the iac valve cause symptons of 1. high rpm over 1000 2. low rpm 1000 or less 3. car shakes when its on 4. lack of power like if the car wants to shut off while you driving it or not driving it. ??? 5. motor feels weak like if it dont wanna stay on feels like if it want to shut down?? 6. can it also cause battery to die out also?? sorry just curious to know please help me on this one. thanks for your time and patience god bless.
HI Great Video very detailed! 2 quick questions please? 2001 Nissan Maxima. In park the rpm's go from 1200 to 1800, back to 1200 back to 1800. It does this very quickly and does not stop. Is this a symptom of a bad or crudded up IACV? Also I read one place that replacing the IACV could short the ECM or maybe when it fails it could short the ECM, have you ever heard of this? I'd like to prevent a shorted ECM from happening if possible when I go to check and possibly replace the IACV. Thanks a lot!!
Good Morning, I have a 95 Maxima. Does the Idle Air Control Valve always give a code? Car is not registering any codes. Have to pump accelerator when car has sat over night, rough idle at red lights. If I move it to neutral, car smooths out. Car runs ok once I'm not longer at the idle. Any ideas what could possibly be the problem? Any ideas will be greatly appreciated.
kfjones58 Not necessarily. You can have an IACV going without a code showing. Rough idle can be a number of things. Try cleaning the throttle body with throttle body cleaner. Also check the pcv valve and egr valve. I have vids for both. Just search my page. If you still have problems let me know
Thanks for your response. I took it to Nissan for a diagnostic. They came back with Misfire coming from #6 injector is not spraying. Do you think this could be the problem also? I have an appointment for Tues to have it replaced.
Thank you for your informative video. In regards to the last step, how can I supply power to the IAC without removing it completely (since mine is part of the throtle body assembly) using a multimeter to see it actually mechanically moving? Thanks.
in Nissan sentra 2003 should idle valve axle go out or go in after switching on because I have rpm problem and note that my idle valve work opposite the video '''putting car on universal computer found no DTC ,,,my idle rpm 1000 and fluctuating while driving if I release petrol pedal on gear
Dear guy, My Mitsubishi Galant year 1990 has a problem the rpm not stable in idle. When give load like AC ON or Head Light ON or move the wheel steer the idle rpm will run rough up and down excessivelly and sometimes the engine shut down by it self. I already changed the Idle Valve sensor 2 times and check the resistant is ok. The output power from the plug is 12.5 volt, but the problem still exist. I checked the movement of the Idle Valve sensor plunger but it movement was only shaking and not extend or retract. Is the ECU bad ? Please your suggest. Thanks alot. John Purwanto, Tangerang City, Indonesia.
I got question guys. I got a 1998 5.7liter GMC Suburban. My idle seems to be a little high, it's idling now more or less at 1300 sometimes seems like 1500 , Do you think that the idle control valve could have something to do with this issue? I was thinking maybe it was possibly stuck open.. Thanks ahead again guys, you guys are always highly appreciated! 👍
I guess I have the same problem, sometimes when I let off the gas to freely wind down (like at the stop light) the engine stalls. No code, but when the ignition is on - the IACV is buzzing, so I think it's sticking sometimes. Thanks for the explanation in the video ;)
I was having idling problems with no code in my gmc sierra. I changed the valve after my Pinole shot out doing the last step of the video. New valve fixed my idling issues.
Primary causes for vehicle shutting off is fuel pump, injector(s), idle air control valve and the ignition circuit. For your particular case, I'd start with the idle control valve. Also check the pcv valve.
Excellent video, very helpful, a mechanic told me that after a replacement, The computer should be reset? it is a mitsubishi outlander 2003. is this neccesary? how reset the computer?
Great video. I tried to remove the iac from my car but I stripped one of the screws. Any ideas to get it removed? Tried using pliers but couldn't get a good grip to loosen it up. Thanks in advanced!
I have a 1998 Toyota rav 4. It idles fine, but when I put the gear to Drive or Reverse, the idle always drop & will go up again. Sometimes the engine will die. I cleaned the throttle & the IAC valve but nothing happened. What should I do? Should I replace the IAC valve? Thank you.
+Dominique Williams Sure could be. If it turns out to be okay, other things to check is the mass air flow sensor - th-cam.com/video/ewjO9JVr8NU/w-d-xo.html - fuel and ignition system.
Generally, it'll be in your service manual. I'm looking at mine and it's at the beginning of the chapter that tells you how to test it. Probably google it as well??
omg this is so helpful right now my car is idling like.3000 rpm I just replaced the throttle body part but trying to figure out why it idles so high when I turn it on
Jorge Camacho I got a new one and mine stopped hunting rpms thankfully . I tested it and ohms were higher on new one than the faulty one by 10 ohms. I don’t know if that matters.
So I have a 99 gmc sonoma. And she runs great. But! Every day coming home from work the rpm surges when I'm doing over 70mph. My gmc does not have the check engine light on or any other. And when the rpm surge happens she has power. No transmission slip she takes off and when I step on the gas it goes down to normal speed but continues to surge.
I have a 94 ranger 4.0 that has a very bad idle. Also when I hit the brakes hard it stalls out but only if its low on gas. I can replicate the stall every time but only when its getting close to e. If it has a quarter tank or more, it will not stall at all Sometimes when im at a stop it will jerk. Not sure if thats related. The iac valve looks super clean almost looks brand new. The only code its throwing I looked up and its mass af sensor which I already replaced. Also I can smell that its running very rich.
WaterWhipin Sounds like the fuel pump pickup is toward the rear of the fuel tank. When you're low on fuel and nail the brakes, the fuel is being forced away from the fuel pump pickup point and stalling out. Try to keep enough gas in the tank or you can burn out the fuel pump. The fuel acts as a lubricant for the pump. Regarding the rough idle, first thought is the idle air control valve. Other areas to look at include the fuel pressure regulator. EGR valve and PCV valve (I have videos for both) or you could have a leak at the air duct causing the MAF code. A bad idle can take some time to diagnose.
CarsNToys thanks for the response. I have good fuel pressure, im not sure if thats an indicator for needing a fuel pressure regulator. I checked for vacuum leak couldnt find anything. I got the truck a year ago and the guy told me about the issues the truck had and I asked him if it might be the fuel pump he said that he replaced it but Im not sure how long ago or if it was installed properly. Thanks for the ideas ill give those videos a look
I like the video, only suggestion would be to go a bit slower when showing where this part 'lives' and zoom in from wide view towards the part/area of the car you are working on. But great Info!!
i just replaced mine now my truck wont start seems like its not getting no spark also aren't u suppose to disconect negative battery cable from battery to prevent damage to the sensor
after replacing the sensor you will have to reset the KAM. this will make the pcm relearn its position. IAC is a stepped motor and it must relearn its position according to fuel trim and A/F ratio.
Thanks for the tip on Ohms. I bought a new one and my car did not run well. I tested the new valve (mine had only 2 pins) and there was almost no resistance.
Please can someone help me. I have a 95 mit eclipse sr I dont have power to the idle speed control. I replaced it with a new one, still no power, new computer, power turned on but its out again, checked all the wires, put new connectors....
I dont get any code.if its plug in car idle vere low when braking en dies somtime,but when i startup idle very good. Now i unplug it an never dies anymore or no low idling but keeps idleing high.idle at almost 2000 rpm in P or N in D it stays on 1100 rpm
+Gravedigga114 That could be good or bad. Check your factory service manual to see what number you should get. On my FSM, it states "approximately" 22ohmz
@@vinaycx According to AllData resistance between terminal 2 and 1, terminal 3 and 5, and terminal 4 and 6. Resistance should be approximately 30 Ohms at 68 degrees Fahrenheit. Hope this helps!
My car was idling at 1100 rpm and i had the code p0505. i replaced the ACV and the car now idles at 650-775 rpm; however i still get the p0505; what could be wrong?
You just saved my Pathy. This old video is a gift that keeps on giving.
Is it an R50 ?
I like your videos they are real clear and not music, clear images,nice,just few like you thankyou
My 2002 Buick Rendezvous RPM jump up and down at come to a stop
78a GOING ON RIGHT NOW I'LL COME AND TELL YOU
Very well explained. Thank you. Found code for IAC on a vehicle that i was working on today. Engine is really rough. Multiple misfires, running rich and whatnot. Perfect time to perform test.
Excellent video sir. Very detailed and well-edited. Thanks.
This is a great video. I've been working on an idle issue on my mercruiser boat engine. Someone explained to e that I should check for power and resistance on my wiring harness at the IAC. I had no idea how to do that until I watched your video. Great attention to detail. The inset camera view as you test for resistance is a great feature! Thanks a bunch!
rossi7r
Best video instruction for IAC valve I've seen.
What are the part#'s for the 5 screws that hold the IACV to the Throttle Body? I messed up those phillips head screws removing them cuz they were a bit stuck. 2001 Maxima GLE
Thank you for showing the way to test the IAC. I am going to test mine tomorrow. I was really worried that I was going to have to replace the part and I don't have a lot of cash. SUBSCRIBED!! And please keep the videos coming this one was very informative.
Excellent video !! Thank you very much !!!
Would be the same test for a two pin set up. 2001 ford ranger 3.0l I put in a new one and still getting the code and running really bad. I''m thinking it might be a bad ECU. Any thoughts
Greg Seleen Did you figure out what the problem was? I have a 2000 Ranger with a 3.0L.
Great explanation... I followed your last test. When I turn on the ignition I hear the IAC click and if I leave it in the ON position for a few secs without starting the engine, the IAC clicks back to the off position. Is this normal behavior? Thanks Jake
Thank you for your very good information. Was easy to follow so I think it’ll be easy to copy. Thank you.
Thank you for the video. Quick question, I was getting P0505 too and bought a replacement part on Amazon. No more p0505 code but this particular IAC makes noise when the key is set to accessories. It sounds like a little motor is constantly running. Is that normal or should I ask for a replacement?
Do I need to reset my computer on my 1999 Subaru legacy outback, after I check and clean my IACV? I didn't actually remove it all the way but after reassembling, my car is now acting like my battery isn't working for a minute. It starts but immediately dies. When I try to turn over again, it acts like I have a dead battery but if I wait a second then try again, it starts but not in a strong way. I know my battery is fine because I just got it tested. When my father and I replaced and adjusted my TPS the other day, we followed the recommended computer reset protocol and that got rid of the At Oil Temp and check engine light. It is shifting so smoothly now and all seemed perfect so we decided to see if we could clean the IACV, we were concerned we might screw it up so just shot carb cleaner into it and then put all the hoses and sensors back into place. Seemed to be fine until the next day when I went to start it and experienced it dying and then having issues starting. I've never had an issue with it starting. Wondering if i should've done the computer reset after messing with the IACV too. Or perhaps we didn't put something back correctly? Anyone have any advice here?
Thank you! Looking at a car with no real issues except an IAC code. Your video has LOTS of testing info, and the picture-in-picture was a NICE addition. Very informative!
All your testing checked out for me except for the last step at 5:20 on my 95' 3000GT. When I turned the car on several times, the shaft did not move at all. I decided to try it again and the first time I turned it on, it moved ever so slightly but wouldn't move again after I turn it back off and on. Is this an indication this part needs replacing?
Sounds to me it needs to be replaced.
+CarsNToys OK thanks, hopefully it fixes the reason why my car is shaking at idle and lacking power
Does the 2006 lexus gs300 have the IACV ?
I can't seem to locate it
on the diag device what is meant by actual stepper motor value?
Does this work for motorcycles as well? I’ve took my IAC valve of and left it connected..when I turn the key to on position, it doesn’t move at all..
Side note: I’ve been having problems with my motorcycle not being able to idle for more than 5 seconds..I changed everything but today I decided to check the IAC valve and it doesn’t move on the key on position
Question regarding a 2002 Nissan Sentra GXE. The resistance check is good and the voltages are good. I have removed the valve to check if it moves when turning the ignition on/off and it does not move. The valve was taken off of a working car. Any suggestions?
Mirko Miljanovic If the valve doesn't move then you'll need a new IACV.
Sir. I wont now this 2pin 12v coming from ecu if is change by mistek is any problem for iacv fungtion?
Does the iac stay buzzing in the in position?
Nice video. Direct to the point unlike others it takes 30mins just to explain this🙄
Great video, but I need to go a bit deeper. I want to learn exactly how the IAC steps, they are not simply fully open or fully closed, they can be set to various positions by the ECM to get different idle speeds.
Yours has two sets of 3 pins. Pins 2 and 5 have 12V to them, then I guess a Ground signal from the ECM on pin 1 half steps the valve in one direction and then a Ground on pin 4 puts the other half step in that direction. To move the valve the other way, the ECM applies Ground signals on the 3 an 6 pins in a similar fashion.
Is that correct?
I have a GM 1987 2.8L V6 Fiero. My IAC valve has only 4 pins. I want to make a setup to actuate the value on the bench. My brother is an instructor at Porter and Chester and he would like to have a little set up to demonstrate how IAC valves work to his students. So learning how they actually work is the first step.
I read 50 Ohms across each pair. I guess one pair moves the valve in one direction, and the other pair moves it in the other direction - but not quite, read on.
I took some baby steps and tried it with 5V first... no action. Then I tried it with 9V (to be safe).
One pair of contacts, still no action, but on the other pair puts a small twitch on the plunger in one direction (even if I reverse voltage polarity on the pair, it still twitches in the SAME direction).
Ok, I guess it does use 12V, but seeing just a twitch is on right path. But the twitch was rotational on the plunger NOT in or out, and again, I expected it to twitch in the other direction using the other pair of contacts - but not the slightest twitch with those contacts!
So, before I try it at 12V, I need to get a better idea on what signals/timing the ECM puts on the IAC valve to actuate it.
There appears to be no position feedback from the valve to the ECM.
I guess on power up, the ECM steps the valve many, many times to get to a fully open (home) position, and then the ECM keeps track of the step pulses to determine its position from then on - until power off.
I have used stepper motors many times in the past, and that is what is nice about them, you don't normally need any feedback because the are dead on accurate on the position (and knowing it's position) if you pulse them properly. But I have no operational specs on my IAC valve.
Any ideas?
Thanks.
I cannot Express how thankful i am for these videos you taught me so much!
Ok last question...? I took off the IAC itself, and there is a little coolant on it and inside the housing. Is that ok as coolant runs through part of it, or should it be completely dry?
What kind of vehicle you working on?
2000 Maxima SE
CaretHalfgem
I haven't come across that on a 4th or 5th gen Maxima. They're usually bone dry.
Actually i found it it should be bone dry. It's been seeping coolant into the throttle body and in be engine...
And when i pulled the TB off, I found all sorts of coolant basically caked in there. I cleaned what I could and shot a lot of Seafoam inside to hopefully loosen more.
i rerplaced my iac on my 2002 SS,,still has a too high idle,,so its on to the next step??? intake leak perhaps???
Does the first test applicable in all 6 pin iacv? Mine is suzuki and has a 6 pin iacv. I wanted to test the iacv coz my engine when running for 30 mins there's a problem occure like when you press the accelerator a little bit the rpm will surge to 1800. Also I notice that when the ac compressor cut off the rpm also surge to almost 1800.
hey just saw this awesome vid. but I came into a problem. did everything you did and everything thing checked out cleaned it up a bit then put it back in but still have code showing. any advice?
Stephen Horton you must clear codes after each replacement fix to see if it comes on again
I tested the IAC VALVE like you did in the end of video. And it only move left to right not out and in. Does it need replaced? Can I send you a video of what it does so you can see what it does thanks.
Yes need to replace
Thanks man 👍. U are more helpful than the repair manual. Excellent presentation
Hey man i have a question. I did the last test and the pintle shot out of the IAC. Is that because i was stupid or something else every time i turned the car to the off position it would go out so far then it shot out still trying to find it as we speak.
I have a 04 Ford Freestar that will act like it's running out of gas at first cold start. Fuel pressure is fine. If I hold RPM's at 3000 or more for a minute it will be fine but RPM's at idle are jerky. No check engine lights are on. Sound like the IACV to you?
Thanks
+Paul Brownfield I'd check the iacv and pcv valve
your very detail about your videos there great.. i was hoping you could help me out. i had a stuck idle pulley it was melying the blet. change it works good now. but i noticed that my 2003 dodge durango truns off now when im at stop. also if i have it on park and give it some gas about 4,000 rpm it dies... i was told to adjust idle. would you know how yo do that.. i was also told that i should just clean the throttle body and iac.. any recommendations.. thanks
Great video. Buying a good digital meter paid off with its first use. Since my Eclipse GT wasn't throwing any codes, but wouldn't idle, I needed to test the part I thought might be the culprit. This video showed me how to do it. New IAC= Big smile & big savings!
Sweet! Glad to help.
Good good video, T have a 01' Mazda Tribute 3.0. Idles rough, checked IACV clean inside. No power at key ON!
Im on disabillity, things are tight like most places. That fuse on the IACV also tends to EEC, VPWR, EVR, MAF, ( bulkhead)?
Most abbreviations I'm familiar, but EEC , EVR? V power ! I guess ?
Ha ha it starts right up! 5 seconds later it starts to stumble to death (dies)! Plz sir i need help .
Great video, you test for power in the sensor, the sensor has 6 pins, you only showed the two for power, what are the others 4 pins that you did not test, are they 2 grounds and two signals? Please let us know and what are the voltage of those others pins, thank you. Cheers from ontario ca
tiny movement 😓 .. wondering if its like the other cars ( long extension ) and by pulling we can determine its stuck or jammed
So this must be the winding noise I hear...I just installed a repaired ecu from ebay and my car won't stay on unless I give it gas once it warms up it will stay on...where can I get a new one iac and why is the ecu not calibrated to work right
@ carsntoys - I have a 1998 Ford Explorer XLT that idles poorly when cold & only a little better when warm. Is the IAC the problem, or O2, or F/A sensor or "all of the above" ?
No Hate On's Please.
+Tony Penner Is the check engine light on? If so, what are the code(s)?
+CarsNToys - It was the O2 sensor 1, bank 1. I replaced it (with much grief), with a new one & seems to idle ok. I then took the negative battery cable off for 5 mins., but the check engine light is still on, but the system says all is ok.
Tony Penner
Glad it worked out. The light will go off eventually. Just has to cycle.
Could you please help me locate the IAC location on 2002-2005 Audi A4 1.8T B6 Model? mine is 2005 B6 and I am having terrible time with my idling. Every effort to locate the IAC has been unsuccessful
Question: I have an IACV that's got only 4, not 6, terminals. So I did the ohms test on 1 + 2, 2+ 3 and 3 + 4. 1 + 2 and 3 + 4 showed about 53 ohms, but 2 + 3, nothing. Does that suggest a fault? Thanks.
Hello. I have the same facts. Have you received an answer?
same scenario here. what was the verdict?
i replaced the iacv with a used one and still the same problem, at cold starts it stalls until it warms up, no vacuum leaks. what else could it be or should i have replaced it with a nee iacv? thx.
Can you show how to check harness for short to ground and short to power? This is actually the next step someone should do after doing the methods you showed. Thanks.
Thanks for the fast response I really appreciate it. Would you happen to have a video on the vacuum hose and valve you are speaking of. Thanks again
+doug resha Unfortunately I don't. The Maxima I usually work on is older and doesn't have this vacuum hose.
Great videos. I have a P0505 hard code which I believe has something to do with either the ISC motor and/or ECM. But before I fix this code and spend lots of money, I noticed that all four of my readiness monitors are NOT complete. I understand the procedure to reset these readiness monitors, but do I need to repair this P0505 first BEFORE I can run the readiness monitors? Is there another option or procedure to reset these readiness monitors first?
I know I can get several other codes when the four readiness monitors are run, but is there a way to reset these monitors so I have an idea of what else is wrong with my vehicle? I don't want to spend money to repair code P0505 ONLY to find out other codes later when the readiness monitors are run. Please help.
would that be the same for nissan pulsar n16 motor
Instead of a replace an entire IAC, along with all the coolant chambers, can I just remove the two screws and replace the coil portion by itself?
If it's replaceable on your vehicle, absolutely.
+CarsNToys yep. I have to buy the entire piece, but it is easier than removing the entire throttle body to get to it.
OH! Thank you!!
Hi David, in my car, the coil part is easier to remove than the entire IAC. I did a test, the harness was getting 11v, some pins on iacv was having 30ohms while some had 29ohms. While car was idling(though rough idling), I unplugged the iacv harness, i didnt notice any change. If I change only the coil, will the effect be same as changing the entire iacv?
I have a 2002 Nissan maxima, I cant find the iacv, ibthought it was connected to the throttle body as it is on the 2000-2001 model
how you're doing I have a 1996 mercury grand marquis gs and it's making a very loud humming noise and I thought it was a wheel bearing but it wasn't a wheel bearing they said it was a idle air control valve so all I have to do is just change it and it will eliminate the problem
I'm getting the code to suggest mu iacv us bad. When changing out the iacv am I required to install a new ecm? I've read in several place I should, but your vedio didn't suggest it. Btw, I talk your video as gospel as you do amazing work. One last thing I have a 97 infiniti i30 if that matters. Thanks.
Bobby Gee Thanks man glad to help. No need to install a new ecm if the IACV is the only issue.
+Bobby Gee Did you get this fixed? You need to check the ECM if its bad also. When the IAC goes bad, it shorts out the chip in the ECM (this is a common occurrence in maximas and i30s). You'll see a burned chip if you take out the ECM. GL
Good Video work with the Picture In Picture (PIP) showing the details of the testing the connectors. Those details make all the difference when trying to learn what you're doing. The are a lot of instructional videos on TH-cam but the camera work is so bad that your not able to see what exactly that the person is working on. I appreciate the extra attention to detail for learning purposes. Keep up the good work
Thank you very much!
I have the code and replaced the iac # 530 306 57ab on a 1999 dodge Durango. After spraying carburetor cleaner all over the carb and cleaning it and putting on the new iac it will not start at all. The security light is on. I disconnected the battery to reset it still won't start.
I tested the prongs on my Idle Air Control Valve and they read 42 to 46 Ohms on each compared to your 30. Same model of car (Nissan A32). Is that something to be concerned about?
Also, when removed but connected to the harness, it moves, but not as much as in this video. It's possible that's just a subjective observation, but if it really doesn't move as much, that a cause for concern?
+Antonio Java The 30 ohms reading can vary depending on temperature. And if the valve is moving back and forth, and you don't have a trouble code for p0505, I wouldn't worry about it.
+CarsNToys Thanks, man! :) This helped me a lot in troubleshooting my car problem. I actually don't have a code scanner, so I had to do things the old-fashioned way and checked every possible point of failure one by one, including this part (which turned out to be fine, based on your input :) ).
+Antonio Java Good stuff man. Glad to help!
my car idles like crazy and stops on me its a 96 nissan maxima if i clean ghe iac will it help i cleaned first half of my throttle but didnt take it fully apart to clean.other side any tips? i really need to fix this
Any trouble codes?
+CarsNToys yes i have a check.engine ligbt i need 3 replacr.my.Egr.tempersture sensor? can it do.with that
I have done all does test and i get 30 ohms and 12v on the harness and i still get the p0505. I even bought a new IAC but no luck. I also tested the continuity from the harness to the ecm and it was good. What can it be?
Its on a 97 Mitsubishi eclipse gst
James Jimmy Did you erase the code and it keeps coming back on?
CarsNToys yes i erase the code and do a drive cycle and the same code comes up. I need to clear it to pass smog.
James Jimmy The only thing I can recommend is see if you can get your hands on the factory repair manual. Maybe there's something else to look at on your Mitsubishi. Out of curiosity, any other trouble codes?
nope only the P0505
I checked mine it does shows everything you've had explained but still have the problem.& the scan shows a bad iac what it could be i already cleaned the EGR as well but i don't see any changes. Any suggestions???
What kind of vehicle? Any other trouble codes?
CarsNToys its a 95 gmc sierra 2500. 7.4 .& since is an old model it doesn't show any other codes.
Gotcha. On your vehicle try doing an ohms test on the valve. Grab a digital multi-meter and see if you're getting resistance. Here's another video showing how to perform an ohms test. Fast forward to 50 seconds: th-cam.com/video/j-Wr2VMvfbc/w-d-xo.html
What if im not getting a code but i suspect the IAC valve?
My Camry 2004 Le is throwing P0505 error code. I just replaced throttle body. Do you have suggestion any fix/suggestion for Camry.
does the iac valve cause symptons of
1. high rpm over 1000
2. low rpm 1000 or less
3. car shakes when its on
4. lack of power like if the car wants to shut off while you driving it or not driving it. ???
5. motor feels weak like if it dont wanna stay on feels like if it want to shut down??
6. can it also cause battery to die out also??
sorry just curious to know
please help me on this one.
thanks for your time and patience
god bless.
HI Great Video very detailed!
2 quick questions please? 2001 Nissan Maxima. In park the rpm's go from 1200 to 1800, back to 1200 back to 1800. It does this very quickly and does not stop. Is this a symptom of a bad or crudded up IACV? Also I read one place that replacing the IACV could short the ECM or maybe when it fails it could short the ECM, have you ever heard of this? I'd like to prevent a shorted ECM from happening if possible when I go to check and possibly replace the IACV.
Thanks a lot!!
Just had the same problem on my 96 maxima iacv disrupted my ecu got another one from eBay along with the ecu put me back in the game💪🏿
Also check your tps
Yes, I ended up replacing the IACV and having the ECM rebuilt....
Good Morning, I have a 95 Maxima. Does the Idle Air Control Valve always give a code? Car is not registering any codes. Have to pump accelerator when car has sat over night, rough idle at red lights. If I move it to neutral, car smooths out. Car runs ok once I'm not longer at the idle. Any ideas what could possibly be the problem? Any ideas will be greatly appreciated.
kfjones58 Not necessarily. You can have an IACV going without a code showing. Rough idle can be a number of things. Try cleaning the throttle body with throttle body cleaner. Also check the pcv valve and egr valve. I have vids for both. Just search my page. If you still have problems let me know
Thanks for your response. I took it to Nissan for a diagnostic. They came back with Misfire coming from #6 injector is not spraying. Do you think this could be the problem also? I have an appointment for Tues to have it replaced.
thanks for the time you took to help others learn
Glad to help.
When he activated the IAC at the end, I didn't see anything happen. What did he see that is not on the video ?
Thank you for your informative video. In regards to the last step, how can I supply power to the IAC without removing it completely (since mine is part of the throtle body assembly) using a multimeter to see it actually mechanically moving? Thanks.
MrDoNHS You can supply power to the valve and you should hear the valve turn on and off. Give that a try.
in Nissan sentra 2003 should idle valve axle go out or go in after switching on because I have rpm problem and note that my idle valve work opposite the video '''putting car on universal computer found no DTC ,,,my idle rpm 1000 and fluctuating while driving if I release petrol pedal on gear
Dear guy, My Mitsubishi Galant year 1990 has a problem the rpm not stable in idle. When give load like AC ON or Head Light ON or move the wheel steer
the idle rpm will run rough up and down excessivelly and sometimes the engine shut down by it self. I already changed the Idle Valve sensor 2 times and check the resistant is ok. The output power from the plug is 12.5 volt, but the problem still exist.
I checked the movement of the Idle Valve sensor plunger but it movement was only shaking and not extend or retract.
Is the ECU bad ?
Please your suggest.
Thanks alot.
John Purwanto, Tangerang City, Indonesia.
I got question guys. I got a 1998 5.7liter GMC Suburban. My idle seems to be a little high, it's idling now more or less at 1300 sometimes seems like 1500 , Do you think that the idle control valve could have something to do with this issue? I was thinking maybe it was possibly stuck open.. Thanks ahead again guys, you guys are always highly appreciated! 👍
Thanks for the video. .my iac went out and because of you I had the knowledge to test and replace it thanks again
+Jean Gimenez Glad to help man
is it possible for the iacv to be bad and not throw a code? being told to replace mine without the code.
Yes, it's possible. I'd test the valve regardless. Good luck!
I guess I have the same problem, sometimes when I let off the gas to freely wind down (like at the stop light) the engine stalls. No code, but when the ignition is on - the IACV is buzzing, so I think it's sticking sometimes.
Thanks for the explanation in the video ;)
I was having idling problems with no code in my gmc sierra. I changed the valve after my Pinole shot out doing the last step of the video. New valve fixed my idling issues.
That was a great video. 👍🏼
heres my situation, i have 2003 toyota camry 4 cylinder and it wont idle after my battery is disconnected, any recommendations?
z9099 It doesn't idle after the battery is disconnected?
i will disconnect battery, then reconnect, and my car will not idol and shut off
Any trouble codes?
not that im aware of...i dont have a scanner if thats what your asking
Primary causes for vehicle shutting off is fuel pump, injector(s), idle air control valve and the ignition circuit. For your particular case, I'd start with the idle control valve. Also check the pcv valve.
My voltage is 12.8 volts is that ok? I'm also getting a reading of 29 on connectors 4 & 5. Is that ok? I'm getting 30 on all of the rest.
+Errol Dillon Perfectly fine.
Thanks for getting back to me so quickly! You're the best!!!
Excellent video, very helpful, a mechanic told me that after a replacement, The computer should be reset? it is a mitsubishi outlander 2003. is this neccesary? how reset the computer?
Great video. I tried to remove the iac from my car but I stripped one of the screws. Any ideas to get it removed? Tried using pliers but couldn't get a good grip to loosen it up. Thanks in advanced!
I checked mine with just turning the key and now im getting a check engine light that i did not have before so what do think happened?
I have a 1998 Toyota rav 4. It idles fine, but when I put the gear to Drive or Reverse, the idle always drop & will go up again. Sometimes the engine will die.
I cleaned the throttle & the IAC valve but nothing happened.
What should I do? Should I replace the IAC valve?
Thank you.
+Vincent Rodriguez It could be the IACV. Is the check engine light on? IF so, what are the codes?
I have a 01 ford Explorer everytime I slow down and stop it's chokes out and stop. a lot say it can be this . can that be the issue
+Dominique Williams Sure could be. If it turns out to be okay, other things to check is the mass air flow sensor - th-cam.com/video/ewjO9JVr8NU/w-d-xo.html - fuel and ignition system.
my 98 acura idles for like 5 seconds then immediately shuts off. while its on you don't hear any rough noises. but you do smell gas. any suggestions?
+Key Monteiro I answer your question here th-cam.com/video/Eps7jk05aWw/w-d-xo.html
It would be helpful if you told us what kind of vehicle you are working on? Ford, GM, or what?
Nissan something
can you test resistance with the valve removed?
KAM?
Yes. The procedure is the same.
Thanks bro .I managed to repair the 1 g eclipse. like your video hello hungary
Thank you so much for this video , I have a 93 Summit with this part on it . This really helped.
How do you know its supposed to be 30 ohms? And does that number differ from vehicle to vehicle
Generally, it'll be in your service manual. I'm looking at mine and it's at the beginning of the chapter that tells you how to test it. Probably google it as well??
Interesting ! My 95 3vzfe wont start cold without pedal. Idles hot at 4 to 500 and tends to stall. THANX
omg this is so helpful right now my car is idling like.3000 rpm I just replaced the throttle body part but trying to figure out why it idles so high when I turn it on
+Mely Serrano Sounds like you may need to adjust the throttle position sensor.
I tested for ohms and showes a reading of 28-29 ohms on 1-2, 2-3, 4-5 but 5-6 did not show nothing what does that mean?
Jorge Camacho I think all should show resistance my friend . It must be bad did u replace it?
@@mrsteel10213 I just got on from parted out maxima still have to test it first.
Jorge Camacho I got a new one and mine stopped hunting rpms thankfully . I tested it and ohms were higher on new one than the faulty one by 10 ohms. I don’t know if that matters.
So I have a 99 gmc sonoma. And she runs great. But! Every day coming home from work the rpm surges when I'm doing over 70mph. My gmc does not have the check engine light on or any other. And when the rpm surge happens she has power. No transmission slip she takes off and when I step on the gas it goes down to normal speed but continues to surge.
I have a 94 ranger 4.0 that has a very bad idle. Also when I hit the brakes hard it stalls out but only if its low on gas. I can replicate the stall every time but only when its getting close to e. If it has a quarter tank or more, it will not stall at all Sometimes when im at a stop it will jerk. Not sure if thats related. The iac valve looks super clean almost looks brand new. The only code its throwing I looked up and its mass af sensor which I already replaced. Also I can smell that its running very rich.
WaterWhipin Sounds like the fuel pump pickup is toward the rear of the fuel tank. When you're low on fuel and nail the brakes, the fuel is being forced away from the fuel pump pickup point and stalling out. Try to keep enough gas in the tank or you can burn out the fuel pump. The fuel acts as a lubricant for the pump. Regarding the rough idle, first thought is the idle air control valve. Other areas to look at include the fuel pressure regulator. EGR valve and PCV valve (I have videos for both) or you could have a leak at the air duct causing the MAF code. A bad idle can take some time to diagnose.
CarsNToys thanks for the response. I have good fuel pressure, im not sure if thats an indicator for needing a fuel pressure regulator. I checked for vacuum leak couldnt find anything. I got the truck a year ago and the guy told me about the issues the truck had and I asked him if it might be the fuel pump he said that he replaced it but Im not sure how long ago or if it was installed properly. Thanks for the ideas ill give those videos a look
Good luck. Scotty Kilmer has a bunch of videos regarding vacuum leaks and stalling vehicles. Just do a search under his page.
I like the video, only suggestion would be to go a bit slower when showing where this part 'lives' and zoom in from wide view towards the part/area of the car you are working on. But great Info!!
Appreciate the feedback.
i just replaced mine now my truck wont start seems like its not getting no spark also aren't u suppose to disconect negative battery cable from battery to prevent damage to the sensor
after replacing the sensor you will have to reset the KAM. this will make the pcm relearn its position. IAC is a stepped motor and it must relearn its position according to fuel trim and A/F ratio.
Thanks for the tip on Ohms. I bought a new one and my car did not run well. I tested the new valve (mine had only 2 pins) and there was almost no resistance.
+craze1701 Glad to help!
Please can someone help me. I have a 95 mit eclipse sr I dont have power to the idle speed control. I replaced it with a new one, still no power, new computer, power turned on but its out again, checked all the wires, put new connectors....
If I'm only getting 24 ohms is that bad? I tested it plugged in cranked the key and nothing. I'm getting power to the wires.
What kind of vehicle are you working on?
CarsNToys a 89 supra I've been trying to fix the idle issue /stalling I already replaced the tps
I dont get any code.if its plug in car idle vere low when braking en dies somtime,but when i startup idle very good.
Now i unplug it an never dies anymore or no low idling but keeps idleing high.idle at almost 2000 rpm in P or N in D it stays on 1100 rpm
Mine moves open then closed back. Should i replace it?
No, sounds like it's working to me.
Very informative and well done video! I wish more 'how to' videos were like this.
Thank you!
Michael Vinson
Nicely done video. Concise and clear.
I get 43 ohms resistance on my 99 Maxima is that any good?
+Gravedigga114 smh, yes that is good, from now on take your car to the mechanic shop lol
+Gravedigga114 That could be good or bad. Check your factory service manual to see what number you should get. On my FSM, it states "approximately" 22ohmz
@gravedigga114 it has been long time but if you see this post or anyone else, i have same car and i also get 43 ohms, how did you fix this error?
@@vinaycx According to AllData resistance between terminal 2 and 1, terminal 3 and 5, and terminal 4 and 6. Resistance should be approximately 30 Ohms at 68 degrees Fahrenheit. Hope this helps!
@@Gravedigga114 thanks.
damn good video. clear and easy
Thank you. Hope it helped.
My car was idling at 1100 rpm and i had the code p0505. i replaced the ACV and the car now idles at 650-775 rpm; however i still get the p0505; what could be wrong?
the pcm has to relearn. disconnect the battery terminals and touch them together for 10 sec then run it..