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any ideas on how to diagnose an exhaust/inlet valve leak ? this is my idea of whats wrong but any suggestions ?

i have had this car since april 2013

bought it after being told needed throttle body clean/adaption . these have been done

changed plugs and leads as misfire was detected on cyl 2

constant judder which is more apparent thro accelerator pedal and "to and fro " type motion of car

keep accelerator pedal steady and the revs will rise and fall

compression test cy1 150: cy2 180: cy3 200: cy4 200

was told these are ok by vw tecky peterborough

have small blow in exhaust but problems were here previous to this

went out in the dark and checked for arcing around leads and coil pack none was evident

changed to shell nitro seemed to be better one day then juddery and jerky the next like the ecu values keep resetting not sure if this is even possible

i had a passat many moons ago approx same age i had a similar problem with that which turned out to be a faulty ecu ,any ways of testing an ecu without a known good one to swap over with

my electric windows :have reset them to go all the way down with the two type push button the next day i have to do again

sorry for long post

any ideas greatfully recieved

thnxs mark

If the shell fuel made it better it can't really be a bent valve stem. It sounds like a potential injector problem. You could rule this out by swapping injectors over. I had the window problem too, it can be poor contacts in the switch or in my case just damp in the switch.

I thought when you did a compression test it was not supposed to vary much (I think its 15% off the top of my head) Between the highest and lowest number. looking at those numbers It looks like there is a problem between cylinders 1 and 2 or certainly on 1, These are pretty high compression engines so I would expect to see them all above 180psi

sorted bad fuel filter