Quote Originally Posted by The Slug View Post
Just discovered I have a spark plug hole with water in it causing a misfire, anyone else had this issue?

Just wondered how the water would get into Cyl No 6 hole?
Either from the rain or washing the car......
The plugs dont seal 100% in the holes, they are allowed to breath through cuts in the rubber seal. When it rains water collects in the recess in the head and eventually finds its way into the plug well..... Common problem. Even worse last year with my car and no seals for normal plugs, #1,2,3 & 4 filled up on the way home from silverstone, so it was running a bit rough to say the least when i got home....
The new Audi COP should be much better as the seal is above the level of the cam cover ....