Looking for a bit of help here, have a problem that has developed on the car and just trying to work out what it could be. The car is a 98 Audi A4 1.8T (Auto) with an AEB engine and just over 100k and for the last few days it seems to have developed trouble with its idle. It seems to drop to about 400 rpm and then raise it self back up slowly to normal. Has also stalled a couple of times. I also noticed that i seem to be getting quite a bit of pressure under the oil cap ( if i leave it undone it actually rattles). Car was serviced this weekend which seems to have made it run smoother but hasnt fixed this issue. From doing a little bit of research im leaning towards the PCV being duff but wondering how i can tell for sure? I would plug in my Vagcom but my lead seems to have died which is typical!
Cheers for any help guys