I was coming back up through France last week when after a period of hard driving, I noticed Vmax could no longer be achieved... When I pulled over for a fag break, the car was idling slightly lumpily, and slower than usual causing the valve train to chatter a bit.
Now, when I crank it over it spins quicker on one compression than on the other 5- and it's a compression problem, I've swapped injectors, plugs and ignition coils around, and have sparks on each plug.
Has anyone else lost one cylinder before? I am suspecting a burnt exhaust valve because the inlet plenum and pipes are still clean, and it isn't using any oil.
Also, There was no hesitation when trouble occurred, just a slight decrease in performance, which I initially put down to having picked up some dirty fuel, after a full fill on SP98.
So, valves, or rings- any experience?