engine noise

[Rootie524]

this is probably the wrong place to put this..but im new here..so sorry..haha..

as many of you know..gms 3.1 Ls and 3.4Ls are fairly noise. lots of things are clicking. everytime i start my car it worries me. i dont know the difference between maybe a timing chain noise, lifter spring noise, or just regular valve train noise..or what im really fearing it might be..some sort of piston slap. its not too loud..but how would i know if its piston slap?

a video could be provided to better assist diagnosis.

[bszopi]

If its typical GM piston slap, it will go away once the engine is warmed up.

[DefEddie]

A mechanics stethescope is about $5 at Autozone.
Start sticking the probe to likely places.
Even at the dealer sometimes we don't know where the noise is coming from till we start dissassembling.
The stethescope is handy for figuring out which valve cover to start under.

Like bszopi mentions,piston slap is caused by the piston/wall clearance on aluminum pistons at cold start up. When the engine warms up a bit and the aluminum expands it will stop.

[Rootie524]

yeah its only when its cold and gets better when its warm..granted its still there but hardly audible.

so is this normal and not something to worry about? will it get worse? can i stop it?

[DefEddie]

Depends on what is causing the noise...

If it's piston slap you live with it or rebuild and get the bores checked and probrably different pistons.

[talon2swords]

Like others say, if noise stops when warm, it's normal for those engines.

My 97 and 99 engines make that noise when they are cold. I quit worrying about it.

[bob442]

yeah, i should add myself, my 2005 monte, with just over 80KM, never missed a oil change, 5000km on fullsynthic, and its extremely noisey on start up, so noisey i think i should go complain under warranty. But thats how these motors are!

[DefEddie]

You might also double check that the oil filter you use has a check valve.
Can't remember which,but either the pf52 or pf52s? I think doesn't have a check valve.
Alot of cheaper brands don't use one either,offhand I think the fram doesn't but the fram tough guard does?
Anyway,no check valve could cause slight oil starvation at startup till it pumps up.
Also make sure your using the correct oil,as bearing clearances nowaday's call for 5/20 and 5/30 weights instead of 10/30 or 10/40.
Wal-mart generally throws 10/30 in everything as do most people too lazy to look or that don't know better,not good on the stuff I work on which is oil pressure phased overhead cams. The clearances don't like the heavier oil.

Just something to think about.