Domenic

I've had the car for two years, its always been like this, there is a faint (well loud enough) knocking sound from the passenger side of the engine. if i put my hand on the motor it doesn't feel like a knock, I'd always thought it was an exhaust leak but some friends came over and heard it ,thought it was comming from the bottom end but couldn't tell unless it was in the air (on a hoist). any Idea what it could be ????? :confused: :confused: :chevy


[Modified by Domenic, 2:33 AM 4/15/2002]

ittlfly

could be about anything from a wrist pin to a rod ...does the sound go away when it warms up? :confused:

moffitt

Mine did that, it was a bad catastrophic converter. I found it by smacking it with a rubber hammer. It sounded like a rod trying to get out.

Domenic

ok went for a nice long ride engine got nice and warm the sound is gone and/or not as noticable could this be serious? :confused: :chevy

92corvette

Well, I had a wierd kind of knocking sound that I couldn't figure out for over a year. Really didn't sound like a rod knocking or a rocker or anything else I had ever heard for that matter.
When I changed out to roller rockers I found the problem. One or the valve stem keepers had slipped up out of the groove. It was rubbing the rocker as it travelled up and down.
I guess I'm lucky that it didn't completely pop out and drop a valve before I found it.

BTW, I also once had a bad converter as mentioned above. It was more of a rattle sound only at idle for me. I got under it on a lift with the engine running to identify that problem.



[Modified by 92corvette, 11:36 PM 4/14/2002]

Domenic

thanks for the info!! did the sound go away when the engine got warm? could it be the cat?

Kevin McGrade

It is your passenger side cat, Mine does the same thing

VMAX451

It may just be "fuel line hammer", there was a TSB out on this a while ago. If you have a stethoscope, check the metal canister on the fuel line near the fuel pressure regulator (called the "accumulator"), you would hear it real loud right there. I think the official solution was to isolate the fuel line somehow, but it never bothered me enough to do anything about it.

92corvette

Domenic, I can't remember my sound going away after getting warm. It's been almost 2 years since I had the converter problem. There are 4 votes in this thread saying it may be converter. I suggest picking up a mechanic's stethascope for a few bucks. (mine was $5) and search for the sound. You could probably put the stethascope on the cat without lifting the car also.
Good luck.