Loud clacking sound:(
 

After repalcing my loud dynomax exhaust with a headers/stock muffler setup I notice that there is a loud clacking noise coming from the engine compartment. It doesn't increase with engine RPM and its not ticking like valve. Any suggestion as to what it could be? I thought maybe it was a exhaust leak at the header but I can't find a leak.

If it doesn't increase with rpm's it would be very strange for it to be engine related. That said, I can't imagine what would make a clacking noise in the engine compartment that is not engine related!

Run over any ducks this weekend? Wait, you said "clack", not "quack" right?

I can't think of anything there that wouldn't increase with engine speed... Unless it was just a loose metal piece bouncing around....

It definetly has something to do with engine cycling. With every stroke of the motor it makes a clack. Not as fast as a tapping valve. What a a bad crank bearing sound like? Its not anything loose, but good idea.

When a rod bearing goes completely it makes a sound that could be described as a clack. But that will increase with engine speed.

Tim

Would there be any other sign of a bad bearing? Smoke, funny engine idle, etc.

Could be CV joint. Put it in neutral and coast, see if it's still there. If it is, kill the engine and see if it's there. Your posts seem to contract a little, it doesn't increase w/ engine speed but it has something to do with engine cycling? Can you explain this more clearly?

No other sign except for metal in the oil sump.

Tim

Just took her for a ride during lunch. The sound does increase in frequency a little during acceleration. It does not get louder though. Not a CV joint, I know that sound well. I got a feeing its something internal or a header to head gasket leak.

What would you guys do if it was your car? Compression test, take to a p-car mechanic, drop the motor, or let it go and see what happens?

If you have an automotive stethoscope or hold your ear to a long screwdriver and touch the engine in a few spots, you may be able to zero in on it. On one hand, it could be your chain slapping around, which is not good at all. Have you updated to the carrera tensioners? On the other hand, you have to figure it's been doing it for awhile but masked by the exhaust and hasn't blown yet. You might ask for a $75 diagnosis from the trained ear, but stating up front that you'll do the work.

I have the carrera tensioners.