jd98ls1z

I have a 1998 z28 ls1. On cold start up I've noticed some valve or lifter noise. After the engine warms up it goes away. The car has almost 107K. I only have bolt on mods.. so the engine is stock. Oil changed regularly. Running 5w30 with a fresh change. Oil pressure runs around 20psi at idle or just a hair under...and around 60psi once you give it gas or at cruising speed.

I work at a ford dealership (i know..I'm sorry) and talked to those guys.. they seemed to think a high end oil filter would work. Tried that and still have the noise. Now they are thinking its a weak oil pump and want to put a manual guage on it. I know oil pumps hardly ever fail..so now I'm worried.

Any help or info is great. Thanks guys.

chaman

iTrader: (5)

Search for piston slap.

jd98ls1z

Did a search. From what I've heard it sounds like the issue. Must be normal noise I guess. Just weird since I've had the car since 2009.. and owned a 1999 z28 before that for a few years with the same miles and never noticed it. I mean the ls1 has always had its strange noises.. this just seems a bit louder then normal. Hope it isn't a big deal. Thanks chaman for the info.

Onyx_Black_Z28

iTrader: (2)

I have this same problem jd98ls1z. Sounds like rocker arms or a lifter to me - a fast paced, loud audible clicking sound the first few minutes the car is running. From the reading I've done, valvetrain noise is normal as long as it does in fact go away once the car is heated up. If you find out any new information, I'd love to hear about it.