Every once in a while, my S will start up with a really rough idle that worries me...right away I give it some gas to make sure it doesn't stall and then it is fine...however, I have not given it gas before and I believe I remember it dying once. I have had this problem for probably a year/15,000 miles, and can't figure out any rhyme or reason to it. Once it starts, the RPMs may idle at 1.5 to 2K for a little bit but then it seems to be fine. Any ideas?

 

I had a similar problem with mine. I ended up doing a valve adjustment, and cleanded out the MAP sensor, and so far, the car has ran beautifuly!

 

The car will idle high on startup on purpose. It's to heat up the cat faster because a cold cat doesn't filter well.

If the rough startup coincides with climate changes (a sudden warm day, cold day, humid day, etc) the ECU might just be confused, and you shouldn't give it gas because then you upset its relearning process.

 

hmm...so just let it die if it idles rough?

 

well, only if that's the problem hehe. so, maybe.