Backfire on deceleration?

vegasanthony said

So ive been running my 2000 5.9 magnum efi swap for about 6mo and i recently started getting backfires on deceleration..
Ive been reading on a causes of this..
Exhaust leaks seem to be one reason
And running lean another..

So my question is would a Exhaust leak near the header make it backfire
So badly near the muffler or should i start diagnosing at the fuel system
Seems to be drivers side only
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check out this video of my Dart when it had a tiny unnoticeable leak between the header tubes where they meet at the collector.
Couldn’t hear it, couldn’t see it but once I found and fixed it the problem was gone.
A section of hose to use as a stethoscope/sound sniffer can be a big help in finding small leaks.
So yes, an exhaust leak allowing fresh air into the exhaust system absolutely can cause explosions inside the pipes and muffler.

https://youtube.com/shorts/EMIvqW__Zqs?feature=share