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Is the Check Engine lite on ? 9 out of 10 times this is a dirty throttle body. Carbon builds up enough arond the throttle baldes and in the IAC (idle air contol) and it does not get enough air to idle. The IAC will make up for it but it cant do it fast enough so it stalls. The PCM is programed for a certain amout of steps on the IAC at certain temps. Now when you start the car if the idle is to low the PCM will run the IAC steps up and advance the timing some to try and hold an idle. But as I said it cant to it fast enough if the throttle body is dirty enough.

Thats what I see the most but I have had times when the IAC may be bad or the EGR valve may stick open at idle.
Generally the TPS will not cause that as the PCM has a programed idle speed if it doesn't get a reading from .5 to about 1 volt at idle. Most of the time a bad TPS acts like a bad acellerator pump in a carb and causes a hesitation. Also if the battery has gone dead or been drawn down to a low voltage the PCM can forget the idle IAC setting and has to relearn it which takes some time and of course it wont hold and idle when its relearning the IAC steps. Ron



x2
Great job of explaining that I was going to but didn't want to have to do all that typing.