Car doesn't idle

[paulkrau]

I have an 03 and it doesn't always come back to idle when I put the clutch in. Sometimes it will fall below idle and die, other times it works great. Has anybody had this problem? Suggestions? I've checked the throttle postition voltage and it is between .97v and .98v. Here is a list of most of the mods to the car.

2.3 whipple Gen 2
60lb injectors
GT Pump with modified FPDM kit
Predator Tuner
SCT BA-3000 90mm MAF
JLT Cold Air Kit
ACCUFAB Throttle Body
4lb lower, 3" upper
900 watt stereo system
HID Headlights
SPV 44 Stinger Battery

 

[SVT GI]

Where in MT are you? I can help you take a look at it if you are close to GF.

Have you done anything to it recently?

 

[paulkrau]

Bozeman.

 

[paulkrau]

Not really. Just put the 3" upper on. The car has been doing this on and off since November 09. I thought it might be something to do with the cold weather. The only other thing I can think of is electrical????

 

[cbr repsol]

take the idle air control valve out and clean it with some brake clean several times. Wipe it out with a rag , then let it air dry for 10 minutes . reinstall and that should help. I was doing some work to someones cobra and he had the same problem, once i did that his car ran pretty good with no more stalling or stumbling.

 

[paulkrau]

Thank you. I'll give that a try.

 

[SVT GI]

Does it idle fine when just sitting parked in nuetral? Any "hunting" idle? You may have the old stall problem that was fixed in some tunes by giving the car a hang in the idle. See if you can adjust your drive idle in the Diablo, bump it up a little and see if it helps.

 

[dpj99cobra]

The IAC is supposed to let some air through at idle so the engine will run. When they fail they tend to like to close up and then whenever the throttle is closed the engine gets no air and will stumble and quit.

All that to say, I'd second the advice about the IAC and say that's probably where to look first. If cleaning it doesn't work then they're not crazy expensive to replace but it's been a few years for me since I did that. Even then it was on my '96 GT as my Cobra's has not stuck so far.

Good luck.

 

[paulkrau]

Thanks for all the advice. I'm going to try the IAC cleaning tonight. Hopefully it works. The car does idle fine when I first start it. The problem starts after I have been driving it, then randomly dies or goes back to idling as it should.