i seemed to have narrowed it down to the head. it could be the turbho but i dont think turbos will make a knock/rattle sound if they are going bad. its a z6 in 89 si with greddy kit and zdyne gold. i took the rocker arm cover off(is that what you call it?) and i removed and checked the LMA's and they didnt seem to stick. nothing looked out of the ordinary. could valve lash be off? any ideas? i have been driving the car like this for about a week and it seems to not be getting worse. it only seems to happen when you are on the gas lightly.

WOW look ar super man!!

 

Yeah it could be the valve clearances. Even though it's a tedius process, adjusting the valve clearances wouldn't hurt (if you do it properly.. heh).

Is it louder when the motor is cold?

 

louder when the motor gets hot.

 

Injectors are loud. If you have a mechanic's stethascope then check it out, if not try holding a screwdriver in the same fashion to your ear.

 

its coming from the head. and its not the injectors. its not a tick. its a knock/rattle

 

and the car still runs good with the knocking sound?

 

doesnt seem to be losing anypower. it never really seemed to pull like it was supposed to on the top but my timing is way retard.

 

any other ideas

 

Can you isolate the sound any further than "around the head"? I'm *starting* to suspect that it's your distributor. I've had a couple fail (internal bearings go bad, turn to dust), and they make a similar sound. You'd notice the sound coming more from the distributor side of the motor in that's the case. Just something to look at.

Also, not to freak you out, but there's a *chance* it could be mildly bent valves. For that to happen, the timing belt would have had to break at some point. In most cases, that will cause a lot of valve damage, and valves will stick open, but I snapped the T-belt on my Accord at idle, and after I replaced it, I noticed a bit more valve noise, indicating that things weren't *just right* in the head, but the car still makes good power and hasn't increased its oil use. Color me lucky on that one, I guess...

Just a couple ideas,

Mike

 

well it does make sort of a popping sound at idle and under decelleration that wasnt there before the noise which could mena 2 things

dizzy
or
bent valves

 

If the valves were bent at all it wouldn't idle very well. It would also show up on a compression test.

 

it idles decent. its not like its gonna die if i give it gas. it just pops and fluxuates. when the car is hotter it idles higher.