I have the colin mcrae series and have just replaced the clutch,time belt and done the headgasket.Heads skimmed.While running it in not exceeding 3000rpm and only done 380miles No3 cylinder went down.Expansion tank water bubbling same as when headgasket went garage think it is either head or cracked ring.Anyone had the same problem or thoughts what it could be.CHEERS.

 

Sounds like your head gaskets gone again.

 

Get a compression check done.