Ls1 Csk

I know from being avid in trucks that GM had CSK problems with the LS1 derived truck engines but didn't realize the LS1 themselfs were effected by it. He has it pretty bad. Should he bring it in? I know they will say it is normal but it isn't.

um.... CSK?

um.... CSK?

Exactly what I am thinking. Maybe crankshaft position sensor?? Or another term for piston slap??

CSK= Cold Start Knock aka piston slap
Alot of the ls series motor seem to have this problem to one degree or another. I have it mildly in my 99Z. It hasn't changed since the day I bought it, so I don't worry too much about it. FWIW, I run 10w30 mineral oil year round.here's a link to some good info:

http://www.ls1tech.com/forums/showthread.php?t=185868&highlight=CSK

If Wickeds is really bad or abnormal, and in warranty, I'd have to recommend he do something about it.

the only problem i ever ran into with the LS1 was worn out piston rings. Is your buddies car burning oil??? if so, that is a known problem and if its under warranty they will fix it. but they will do an oil consumption test first. also, even if you just suspect something and the car is still under warrantey, take it in so there is a record of it. if they wait till after the warranty expires to agree with you, you can point to the fact that you brought it in under warrantey for the complaint and they will have to fix it at their cost. as far as the cold start knocking, i started plenty of LS1 engines in the cold and it was never noticeable. in fact i drove a LS6 equipped vette with a snapped exhaust spring and it didnt make that much noise, so if there is a very audible tapping, slapping, knocking sound from the engine, it aint normal. take it in and have it checked out.

although keep in mind that the engine and pistons are made of aluminum, which expands, so they have to design in clearance for that, so it is very possible that the noise is normal. or it could also be injector pulses which from the LS1 baised engines are very noisey.