Thread: Car wont idle?

I'm having a problem with my 2002 gt w/ 138k miles.

Yesterday I drove home from work and my car ran perfectly normal.

Last night, about two hours later I went to meet up with a friend and when I started my car it started right up but died instantly. It was kinda cold last night too, not sure if that had any effect on it.

So I tried restarting it and it started right back up again but again died instantly.

If I would start it up and give it gas though it seems to run fine. If i keep my foot on the gas slightly i can get it to idle where it should just fine. I even used both feet and drove it around and it drove fine. But again, if i took my foot off of the gas it would die almost instantly.

I tried unplugging the MAF and it didnt help.

Some people said I could have a bad IAC valve which kinda makes sense.

What do you think it could be?

Also, this morning I went out to my car and it started right up and idled fine. ???

Another thing I've noticed is that occasionally on cold mornings before the car is fully warmed up, when I'm coming to a stop it will occasionally bounce up and down in rpms a few times when im coming to a stop. then it idles fine. This happens relatively rarely.

So what are your thoughts?

Thanks for the help !

Crank positioning sensor...or a nasty vac leak.

Bouncing tach is a sign of the CPS.

Does the car have any CEL's?

No CEL's.

Where is the crank sensor ? and how can you tell if its bad?

Is it one of those things you just replace and see if it fixes your problem?

*Update*

Car started up perfectly normal this evening after it had been sitting for a few days. I figured I would take it for a spin and after about 3mins of driving it started to die.

Eventually it wouldn't hold and idle even with feathering the throttle.

It eventually died.

When it died the check oil light came on, so I popped the hood and made sure it had oil. The oil was where it was supposed to be. I let the car sit for a few minutes and it started back up rough, but started non the less. It drove relatively normal until I made it back home and turned it off.

Now experiencing this does it sound pretty damn likely now that it is the crankshaft position sensor?

Still no CEL's

Thoughts?

I asked "theothernick" and he didn't think it was the cps. That's why I asked......

It was the mass air flow sensor. I swapped in a new one and it runs perfect now. Not sure why unplugging it didn't help but the car runs great.