dstappity

iTrader: (2)

can't pinpoint it but i think its either something in the intake or the drivers side head, it sounds pretty close to the noise my idler pulley made when it started going bad, which i just replaced today.

what could it be, rocker arm bearings going out?

dstappity

iTrader: (2)

anyone?

DC01SS

Does the rattle stay constent or does it change with rpm?

dstappity

iTrader: (2)

constant, can't hear it when the engine revs

KevinR

If it's like a rock rattleing in a can sound, it could be detonation. Just a thought

dstappity

iTrader: (2)

more like a couple of rocks rattling in a styrofoam cup. it does it louder when the engine is cold and when i barely open the throttle plate it gets louder, not really when the engine revs, if you know what i mean

KevinR

That's werid. Do you have a video of it?

Tommyv8

iTrader: (8)

If it's louder when the engine is cold and then goes away after it warms up then it sounds like piston slap. It's a constant rapid hollow-sounding knocking. My car has had this ever since it was new and it's not harmful or able to be fixed. Very common with the LS1.

dstappity

iTrader: (2)

no video of it, my uncles 5.3 sierra piston slaps and mine doesn't sound anything like that,

KevinR

Yeah, piston slap normally isn't much of a "rattle" sound. Try to get video of it, if you can, and post it up.