Rep Power: 0

Hey guys,

While driving and coming to a stop, my idle drops almost to 0. If I turn the lights on, it goes up to like 400. With the stereo on, it goes up to like 600-700. What is going on here. At first I thought it was a bad battery. But even though the battery was bad, I replaced it and still get the same problems. I have no mods, unless if you consider upgraded 1/0 wire a mod. I do have a system. It's an arc audio 2500 amp (270 watts rms per channel) pushing 3 way comps. I don't have subs (hence no monstrous amp). What could be causing this problem?

 
Rep Power: 811

if you have an 01, most likely you need an ecu flash. otherwise, it could be a throttle body thats dirty.

check here first to see if the idle drop applies to you.

http://www.geocities.com/pfeifferperformance/TSBs.html

if not, try cleaning the throttle body and IAC (idle air control) valve. remove air cleaner, then remove throttle body, the iac valve is screwed on, its the piece that the coolant lines are connected to.. remove and wipe/spray with carb cleaner until the whole thing is clean. let dry overnight, reinstall everything, and reset the ecu/do the idle learn.








PCM / ECU Reset and Idle Learn

1. After installation of throttle body is complete, start the car and drive it until the engine is at full operating temperature.

2. Park the car, turn off the engine, and pop the hood. Locate the fuse box and lift up the top cover. Using the supplied fuse puller, remove the FI ECU fuse for at least 10 seconds.





3. Replace the fuse and close the box. Make sure that all electronics and accessories are in the off position. Start the car and let it idle for 10 minutes with the hood closed. Do not press on the gas or turn on any accessories during this time.

4. After 10 minutes, turn off the car. The idle speed should now be set. Start the car and go drive like you normally would so the PCM can relearn the fuel maps.

 
Rep Power: 260

omg, this doesnt even apply to me but damn, thats great stuff to know. Thanks alot!

 
Rep Power: 811

it will as your car ages. The iac and throttle body will eventually build up carbon and affect idle/power.

 
Rep Power: 268

Hey Gearbox, with removing the IAC valve is it necessary to do the coolant bleed then too? Or is the IACV enclosed and no coolant drains out/air gets in?

BTW welcome back!

 
Rep Power: 811

yup! you must do the coolant bleed because air gets in when you disconnect the hoses. open the radiator cap when car is cold, then warm the car to temp by revving the throttle a little. once its warm, turn heat to full blast and watch the air come out. can also switch the ac on to get the fans going. it shouldnt take that long.