Backfiring popping on deceleration

[lutzy]

Just got my car back after having a cooling system installed and after taking it for a ride it seems to be backfiring and popping out of the exhaust when letting off the gas. It is a 598 BB with a holley 1000 carb. Any ideas? Plugs and wires are good.

[nicks67camaro]

Was there any exhaust work done recently? I have had a backfire / popping when i fixed my x pipe and missed a section welding it up. I know hearing a slight exhaust leak over a 598 BB may be hard. How are the collector gaskets?

[lutzy]

No exhaust work done recentley.. Everything is tight. The engine was running on for a few sec's after shutting off but after I turned the idle down it seems ok now.

[Henesian]

Too much timing? Too rich?

[lutzy]

Timing is set right, plugs Have a tan color so it's not running rich..

[Ron.in.SoCal]

Jetting...

[sam 74]

have you checked for vacuum leaks?

[lutzy]

was a leaking exhaust manifold gasket..problem solved :)