Mk5 GTI rough idle and misfire

[Vag-mk5]

Hello everyone, I have a problem with my gti

If the car stands still for a day and I start it, it has over 30 misfires on cylinder 4 read with VCDS

but only the first 20sec after that nothing more and it runs quietly

and as soon as the engine has reached operating temperature and i brake at traffic lights, cylinder 1 occasionally misfires when idling

so far i have changed the parts and it was still the same error

spark plugs
Ignition coils
Injectors
Compression measurement(good)
Mass airflow meter
PCV
lambda sensors

I really don't know what else to do, please help, thanks

[mjmallia]

The small cam chain and its tensioner.....also the three plastic rings in for the oil pressure to the actuator can all create misfires and rattles.

[Vag-mk5]

Yes, the chain and tensioner were also changed 2 weeks ago

And the 3 rings from the housing also changed

[GVK]

Any coolant loss/signs of coolant on spark plugs?

[Vag-mk5]

Any coolant loss/signs of coolant on spark plugs?

no, there is no loss of coolant or it is not noticeable, I changed it completely a year ago and the level is still between min and max

[Marky050618]

I done my chain a couple weeks back then had this, was driving me potty turnt out the middle of the three rings in that housing broke and cam out and i didn't notice which caused this issue.

[DDale]

Had the same symptoms before, especially the misfires on stop. It ended up being the N80 Purge Valve so might be a good thing to check.
https://www.mk5golfgti.co.uk/forum/index.php?topic=132469.0