Hi all, I drive an Opel Astra GTC 1.6 Turbo with 140000 km on the clock with engine number A16LET. It is a 2012 model and well looked after. I have been experiencing jerking when trying to accelerate hard. It’s almost as if the car is losing power for a few split seconds continuously (only when accelerating hard). I took it to a well know mechanic and he did a diagnostic and saw that the engine was giving a vaccum fault. I then replaced the pcv valve (dumb German engineering forced me to change the whole valve cover). This has helped a lot with the jerking but for some reason the jerking is still there and I have no clue what it could be. I am planning on doing a valve adjustment soon as it is needed and was wondering if anyone could help with the clearance level as I have not been able to find it online and I bought the car without its user manual. Any suggestions would help to why my car could be jerking and also if anyone knows the clearance level it would be much appreciated.