hi all!
i picked up my Dads 02SS...beautiful car...clean...62000 miles...runs great...until it gets warmed up about a mile or two...then she does the idle fuctuation/stalls at red lights ans such....she does fire right up...but i have to feather the pedel to keep it running...but as long as i keep in the gas it runs smooth...even when it cold and i start it and rev it it bogs around 3500-4000 rpms...almost like a rev limiter..
I have since i picked it the CEL was on took it to Advanced Auto and they told me the MAF needed to be replaced....so since then ive:
replaced MAF
replaced fuel filter
changed plugs
sea foam
since the MAF change the CEL hasnt come on but the dreaded stall happens and I am at my wits end...could the CAT be clogged?or starting to get clogged...
she does run strong and smooth until it warms up and i have to let off the pedel at a light..then stall

any suggestions would be greatly appriecated...

 

Typically if the car is stalling but giving it gas keeps it alive, then it's the IAC (Idle-Air Control) on the Throttle body.

 

Doesn't sound like bad Cat to me. That usually shows up as reduced power at higher speed / RPM, not idle.

Start with basics: spark, fuel, air. Sounds like spark is OK if it otherwise runs well except at idle. Air is probably OK, but doesn't hurt to check the air filter just in case. If it were really clogged, it would effect performance more as RPM / air flow went up. You changed the fuel filter, but have checked fuel pressure? Low fuel pressure could make it falter at idle.

Just throwing out some ideas. Hopefully others with more knowledge will chime in.

 

A fine example of someone smarter than me! I forgot about the Idle Air Control.

 

x2 on IAC & cleaning the TB

Don't rule out a bad MAF again, when it does the issue, unplug the MAF and see if it dies

 

thanks for all the great info guys...btw I also changed the air filter...so the IAC would that issue happen after warm up?

 

I would imagine so, because on a cold start-up the car forces a higher idle than when it's already warm. When I had a bad IAC I stopped to get gas and had a hell of a time getting the car to start again.

Then I ran some errands, and couldn't warm-start easily at the grocery store.

But it worked fine on a cold start the next day. But I ordered an IAC and just took the train for a couple days aha.

 

Bumping this thread because exactly as OP stated, I have the same symptoms.
Question as I am on my phone and can't really search well... What does the IAC cost? Thanks guys.
Also, just today, change spark plugs, fuel filter, wires, and pvc valve.
*edit*

which one would apply to my Dale Sr. (3.8 L67)

http://www.amazon.com/gp/part-finder...7791&carId=001

 

Try taking it off and cleaning it first. Just for the hell of it. Carbon might be making it stick.

 

Mike, I will thanks for the suggestion... Is MAF sensor cleaner safe for the AIC aswell?