My car almost died yesterday, I was parked up and someone wanted to hear my high rev limiter so I started my car up and gave it a rev (it was already warm) but as soon as the revs got to around 7k it started to run like a heap and cut out...
I managed to drive it home and was slightly relieved to think its just not firing on 1 or 2 cylinders. Once i got home I took all the coils and spark plugs out, I noticed that piston 1 looks very wet, piston 2 is damp and the rest are bone dry. The spark plug in cylinder 1 is also very black. I tested every coil and spark plug and they all produce a good spark.
After rebuilding it it will now idle on its own (not very well), so I could at least get near the engine while its running and it sounds like there is a massive air leak somewhere, u can hear air rushing out of somewhere and it sounds like its in sequence with 1 cylinder (as if I was running with a spark plug out)
I'm getting a compression tester today so I can carry on fault finding just wondering what ur ideas are?
If it hasn't got compression I guess I'm looking at rings, head gasket or a 'dropped valve' (what ever that is?)
And if its got compression then maybe just an intermittent coil/spark plug?
Any help would be massively appreciated