Rep Power: 242

just have a few questions that at this point i think only a honda technician could answer for me? it would be greatly appreciated!

 
Rep Power: 452

What is your question? Alot of people on this site are techs or have general automotive knowledge. I may be able to answer your question.

 
Rep Power: 242

Well, about a week ago i had to take my car to the honda dealership and have the iac motor replaced because every day for lunch i would go chill in my car and have the a/c on for about 30mins. when i would get ready to go i would turn my a/c off and as soon as i would do that my idle would drop, start shaking the whole car and die. well since i have had it back it started acting like it was fine until yesterday. it died twice, so now after we thought we knew what it was i am just at a loss for words........i dunno

 
Rep Power: 452

Was it your idea to replace the idle air control motor or the dealerships?

If they are the one who told you it needed to be replaced and charged you for it, yet the problem is still there, then take it back and have them find out what the problem is. It shouldnt cost you anything.

Now without being there and seeing the car, I cant really say what it is or what I think it would be. it could be something simple as a faulty sensor or an ECU needing to be updated.

 
Rep Power: 242

Well i work at a dealership (dodge) and when it messed up the first time i had a few of our most experienced techs look at it and they determined it was the iac so i took it to honda because im still under warranty (31,000). the reason that they determined it was the iac is because there is like an iac sensor right next to the throttle body. the car was running like crap and idleing low. when they unplugged that sensor the car started running fine. so i take it to honda and they discovered the same thing plus it did throw an engine code, so they fixed it and now its doing the same thing again.

now it only seems to do this when the car and a/c has been running for atleast 30 mins at idle and its hot as hell outside. i turn the a/c off while the car is still at idle and there goes the rpms.....straight to zero and car starts shaking (sometimes just dies).

the only advise that im getting now is that it seems to probably be a pcm (powertrain control module) which controls engine fuel managment as well as idle speed.

 
Rep Power: 452

pulling the IAC connecter off is a good way to check it, but if you had a DTC stored, I would start there.

Next question is, is the check engine light on?

But also if honda charged you for a IAC and that didnt fix it, take it back to them and have them correct it. Again you shouldnt have to pay anything because you already had it there. Its on there time and money now. if you take it back, it will be a "come back" for the tech who diagnosed it the first time. Now he gets to diagnosis it again for free. But thats usually how it works.

Now usually if the PCM has to be replaced, it is after all other diagnostic steps taken have failed to yeild the problem. Its also the last thing suggested in the honda service manaul for each trouble code. If all else is fine.

But again if the check engine light is on, find out what the code is and I can help you from there. I have the honda service manaul. And just cause there is a code for the IAC, doesnt mean its bad.

 
Rep Power: 242

Ya i did have a check engine light on but only until i had pulled that plug. After they replaced the iac i guess they made it go away.

Basically im just at a loss for ideas,just seems like one of those problems where you have to fix a million things b4 finding the right thing ya know lol. however it is still under manafactuers warranty so im good to go there, this last time didnt cost me a thing except having to find a ride for 3 days! that was

have you ever heard of anything like i described happen before?

 
Rep Power: 452

Ive heard of all types of problems. But usually, with your problem, it happens when they turn on the AC.

usually when a check engine light comes on, there is a list of steps assosiated with that code. it will tell you to check a certain wire for voltage or a pair of wires for continuity, etc.. and based on that reading, is where you go next. if you get a certain reading that is within the specs given, it may say replace something. If the reading isnt within specs, it may tell you to back track in the circuit and check for power or continuity somewhere else. its purpose is to make sure power is getting to where its supposed to and its also checking for short circuits, opens, bad grounds, etc...

It may have been that the technician who worked on your car got to a point where he felt the IAC was at fault, or he may have mis-diagnosed or skipped a step. who knows. its even possible that the IAC was at fault and the new one is faulty too.

But if its under warranty, take it back.

 
Rep Power: 242

Oh ya, i am definately gonna take it back. i just wanted to kinda go in there and give them sort of a boost on the problem. hell, it took them 3 days to diagnose and replace the iac! im kind of afraid to take it back to them but they are pretty cool about my warranty due to the mods. the last dealership i took it too wouldnt even look at it. they popped the hood and said no warranty! lol.

well hell man, i appreciate your help on the matter . if i have anymore questions i will definately let ya know.

 
Rep Power: 811

ya iac almost never goes bad, i bet letting the car idle caused it to clog with carbon. you should not idle a car more than 5 minutes. and i bet cleaning it out would've solved your problem, and reset the ecu and do the idle learn. if i dont do the idle learn my car will shake and rpm will go up and down.

 
Rep Power: 365

look at your spark plugs... as gearbox said, idling for long periods is not recommended and it will foul your plugs among other things.