Ok, my friends 1998 Z28 is making some awful strange sounds. Me or him have never heard anything like this before. It looks to be coming from the back of the motor on the pass side under the valve cover. It sounds like a lose rocker arm but we took the valve cover off and nothing. All the rockers check out ok, no bent pushrods or anything. The car is not down on power, it doesnt act any different it just has this sound. It only does when it is reved up, it is dead quiet at idle.

Any input would be great, thanks!


PS, I have a video of it, if someone could host it or tell me where to go to have it hosted I will, just to give you guys a better idea of what it sounds like.

 

Maybe a collapsed lifter

 

I dunno, I figure it would lose power from that.

Here is a video of it.

http://videos.streetfire.net/Player....C-53836E33C1D3

 

If it's an automatic, check for a cracked flexplate. Could also be an exaust leak.

 

BlkLT1 mine is doing the same thing except it's coming from the rear driverside and it's not as loud as you friends. Has it got anylouder since it started doing it? I haven't had any power loss either. I watched you video and mine does the exact same thing.

 

Its an M6 car. We dont know if its gotten louder b/c we had the cutout open. Do you have headers on your car? We might have found out what it is....

 

Yep it has longtube pacesetters and it's an m6. What do you guys think it is?

 

heh, might be an exhaust leak.

 

Combination frogs/crickets

 

Just frogs cause they ate all the crickets. Now if I could only get rid of the frogs.

 

Well, I think we might have found it. We went for a drive and ran the car pretty hard. We ran it up to about 150 and after he left there was a horrible exhaust leak. He has pacesetter LTs with there gaskets and now if you look at the very last header pipe you can see almost all of the gasket missing. I guess the big load on the motor at those speed blew out what was left with the gasket. B/c now that sound is there but its a lot deeper tone. I will let you know after we get off our lazy butts and change the gaskets.