Just encountered this issue twice today from cold starting the 1.9 aaz 95' passat. It has a relatively fresh motor in it, 1.6td boost pin and spring, with some enhancement to the fuel screw. The IP has the vacuum operated fast idle switch.
About 5 minutes into driving it from cold start, the rpm's begin to jump, drop, jump, drop, etc. Increase is only about 150rpm or so, and mimicks what is supposed to be the fast idle kicking in.
On another note, the fast idle does not kick in immediately upon starting the car cold and usually is on after the 5 minutes or so it took for the idle to start jumping. Seems like the vacuum cannister is kicking in, then off, etc.
Any opinions on how to remedy this situation, and how to get the fast idle to kick in immediately after cold starting?
Topic: Rpm's jump, drop, jump, drop as car warms from cold start (Read 3651 times)
