Within the first 4 minutes of a cold engine, my 96 VW Jetta, has this thing where it will intermittently cut out. If you happen to be stopped, one of two things, if you let it run it's course, then the idle will fluctuate up and down from about 700 to 900 for about 5 seconds, or there abouts, and then the idle goes high to about 1200, for about 5 seconds, and comes down to normal idle.
On the other hand, if you slam the pedal down, and let back up quck, it tends to clear it out, and everything is normal. Otherwise, it runs just fine once it has it's fit.
I've cleaned all the grounds that I know of, and replaced the coolant temp sensor, and throttle body, but not sure what is causing it??
I'm hoping someone might have an idea on what is causing it.
It would almost make me think that it is something that when it first warms up?
Any, thoughts, ideas, or suggestions?