Hello...

Have a BWA engine 3c0 2l tFSI 48,000 mile. Have noticed that there's a lot of suction when I remove the
oil filler cap at unscrewing. And when I remove the cap with engine in idle, engine revs die down and
starts to fire lumpy. Replace cap and tick over is back to normal.

Does this indicate a failing crankcase vent valve? Or is this normal?
Had a search around the forums and the few posts with this engine and fault all speak of being unable to remove their oil filler cap due to the suction and
faults showing up on Vag-Com and a light on the dash. Don't want to get to that stage!

Any experiences or more informed knowledge would be welcome

RichardSEL