i had simular issue when like a t1t i removed the oil splash guard under the cam cover as i thought it was making a racket, well after a few days oil got into the throttle body and when driving and changing gears, it felt like the engine was going to fall out. when i would start the car up it would rev over 2k rpm and snap crackle & pop, after taking it all apart again i realised i had some oil sitting in the throttle body cleand this out and the started it, still same. got someone out to check with proper vag com and he reset the throttle body and since then its been sweet!
does your car rev straight over 2k rmp? does it pop and back fire?