recently, the engine has been making a tapping/knocking noise when very cold. only lasts untill the car warms up and then stops. Car is an STIV with a P1 ecu. Done 30K. Is this the dreaded knock????

 

Sounds more like the dreaded piston slap to me, especially as it goes away when it's warm. Or it could be your belt tensioner. Do a search for piston slap ("they all do that sir...") Well mine does anyway and so do plenty of others

 

I'm gonna stick my neck out here and say that its nothing to worry about. It's definatley not knock but something to do with tappets (I think) Mine has done it since I've owned it and since its been on a rolling road recently I assume that there is no problem. If however the noise doesn't go away when its warm then you have a problem.

 

ta - just read the reports. Feel reassured.