Last December I picked up an 02 Camaro Z28 with only 17k miles on it. I'm in the process of doing Headers and solid motor mounts so I figured for the hell of it I'd do a quick compression test...

Well here's what I found... (Now I know that compression numbers don't mean alot, they just need to be within 10% of each other) Leakdown numbers is where I should be looking if there's a problem. But I figured with only 17k miles there really shouldn't be a problem yet... Oh, also this was on a cold motor that hasn't been run in about a week. Temps are about 40 here.

Cyl 1: 185 Cyl 2: 178
Cyl 3: 185 Cyl 4: 155
Cyl 5: 185 Cyl 6: 162
Cyl 7: 178 Cyl 8: 172

What do you guys think? Should I be alarmed by this? I'd have a hard time believing there should be a problem with the motor yet but you never know...

 

I would recommend a wet compression test and see what numbers you get. Cylinder 4 is without question a cause for concern, and probably 6 too.

 

Yeah, kinda what I was thinking. Once I get the exhaust done I'm probably going to let it get warmed up and do another test. I'll probably just leak down test the thing to and see what's going on.

Kinda funny though that a car with only 17k miles could be having a compression issue already. Oh well, if they are in fact that low, and it's a ring sealing issue, I guess that means I'll be stepping up from the 346!

 

Once you run the engine and check your results warm, you might feel a little better about it. Does the car run poorly, or give you any other cause for concern? If the answer is no, then your next round of tests will likey back that up.

I suppose you could "luck out" and find a valve leaking down, and "have" to replace the heads...

 

No, it seems to run fine. The only thing it does that concerns me is it's got a rear main leaking which could be due to excessive crankcase pressures which could mean blow-by. The two suspect cylinders are 4 and 6 (right next to each other) so I'm not ruling out head gasket issues. I would much rather it be a valve or head gasket issue because like you said... gotta replace the heads... damn lol.