Quote Originally Posted by aaapm2000 View Post
Just a follow on from this one. I had identical issues with a WRX, I tracked it to the MAF sensor. Going out on error during the heat soak after stopping. To prove it its quite simple. When it wont start. pour a cup of water over the sensor. it will start immediately.

I am replacing it at present.
Whew old thread! And boy did I type unintelligibly back then.

The problem with my car then seems to have been a combination of issues. My car at the time had a turbo sx chip piggybacked to the stock ecu. It was on the car since 2002 and was rather archaic compared to something like the Cobb accessport. The owner had told me about the chip, however I never thought to investigate that area nor divulge it to the mechanics. So I blame them for just throwing my money at the problem but not for being ignorant to my car's mods. After talking to a nice man over at turbo sx I decided to pull the chip and see what happened. Low and behold it's been well over a year and I've yet to have the aforementioned problem again.

HOWEVER- Upon starting up a warm engine, I still regularly get a steep drop in rpms to the point of almost stalling. This is apparently a widely experienced problem with this car and I've yet to find out why it occurs. Some believe it's electrical in nature. To this day I don't really know if the piggy backed chip ceased to work properly and consequently because of it's remapping would cause the car to go into some sort of safety mode OR if the chip was working properly but would malfunction simply because of the underlying issue discussed above.

All I know is that my car is a lot more reliable now but a heck of a lot slower. I may eventually pick up an access port but I'd still like to know what the underlying issue is that's causing the drop in RPMs on a warm start up.

Cellphone post so excuse the errors.