Throttle revs up by itself...

[CrimsonBrian]

Hey gurus!
I have been having this problem for a little while now and it seems totally unaffected by weather, the A/C or how long the car has been running. What happens is that when I take my foot off the gas or put in the clutch to stop or change gears, the car reacts as if I have jammed on the gas. It will climb all the way to redline unless I lightly tap the gas in which case it goes back to normal. The car seems to want to accellarate on its own and, needless to say, this is bad. I have no idea what it could be. I have checked where the pedal meets the floor to make sure nothing is caught but that hasnt helped at all. Any ideas? I want to have an idea of what is going on before I have my indy or the stealer give it the once over. Thanks!

Brian

[stu1]

I guess the first thing to find out is whether the throttle is actually open or not. The next time it does it, just switch it off then remove the air intake pipe from the throttle plate to see whether it's open or not. I'd also check it was mechanically sound as well.

If not it's probably your Idle Control Valve jammed/sticking open.

Best,
Stu.

[CrimsonBrian]

Thanks Stu! Although, I have to admit that I wouldnt know the first thing about doing that, I am a total mechanical idiot. Is there some way to grease the idle control valve? Should I just have it replaced? Thanks!

[Kalevera]

ICV.

It's a pain in the ass to get to on the M50 -- underneath the intake. The three lead kind on your car can't be cleaned without destroying it; it needs to be replaced. Also, when you change the ICV, the DME has to be reset, otherwise it will likely work the new ICV as it did the old/malfunctioning unit, and there'll be no noticeable improvement in the problem.

best, whit

[CheapCheap1]

that the ICV will be automatically cleaned, when the rpm is over 3,000???

[Beemr750]

Check or adjust throttle switch

[CrimsonBrian]

Thanks everyone, I'll pull out my Bentley and see if I can figure out where all these items are. Then I will take it to the shop and see what they say. Is all of this going to set me back a bazillion dollars?

[Kalevera]

Hmmm -- once the three lead ICV gets clogged, it's only fit for the trash. The actuator spinning might remove some of the nasty residue that collects on these things and send it down the intake; whatever internal cleaning controls may exist don't guarantee a reliable or consistent lifespan.

best, whit

[ryan roopnarine]

i know this differs from what everyone else says....

i think that your cruise control cable may be falling off, pulling the throttle open when you aren't pushing on the accelerator. there's a safety campaign part for it, if it isn't on properly this may happen. either this, or the throttle position sensor may be going flaky.

lowell....what do you mean when you say you can't clean the three lead icv without destroying it?

[Kalevera]

IIRC, a new ICV is something like $150. It could be another component, but it'd be the first thing that I would check.

best, whit