Ok my 88 TBI camaro has had this nose for a while now. It sounds like it is comming from the passanger side by the manifold. Could be an exhaust leak cause it goes away after the car is warmed up but might knock here and there. I was also told it could be my valves. What is up with that? Am I right that it is just an exhaust leak, or could it be worse. The car has 122K miles on the engine. And i'll be the first to admit I beat the hell out of this car for the simple fact I am putting my old 350 in it. When I slam the gas and it hits second the back tires spin and sometimes I get a little sideways. I love this car. What is wrong?

 

Would you characterize the sound more as a dull knock or a sharp tap?

 

it is definatly not a light tap i is kind of like hitting 2 pieces of metal together with cloth over them. that is a werid way to describe it but aths the best i can do.

 

Dull knock = ?????
Sharp tap =?????

 

Prolly and exhaust leak, as most rod and main noise doesn't go away with temp.

I also heard some noisy hp/hv oil pumps when cold.

 

I would characterize your description as a knock, not a tap. That could be piston slap, a rod or main bearing, or a piston pin.

How long does the engine warm up before the noise is silenced?

 

Have someone power-brake eng slightly while you listen under the hood. An exhaust manifold leak will get a lot louder with a relatively small increase in throttle position.
After the exhaust heats up and expands, it can help seal the leak.

 

would an exhaust leak sound metallic at all?? Cuz I got a nice little noise, sounds like 2 metal things are repeatedly smacking eachother...