What can cause a backfire?

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coachdtierney54

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God I hope not.

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theblindchicken

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Right before I pulled the engine in my truck, I would have a pretty fair amount of that popping backfires while coasting or engine braking.... Popped the hood later while running, had exhaust leaks all over both manifolds. She was running a little rich too, so my guess is the exhaust was hot enough and leaked bad enough to actually cause a little combustion in the exhaust
 

Honky Kong jr

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God I hope not.

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I'd check they aren't to hard to replace on the truck. Remember wash line rope is your friend. It could be something else too but engine braking plays hell on stuff. Your engine is an air pump not a dynamic braking unit.
 

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Right before I pulled the engine in my truck, I would have a pretty fair amount of that popping backfires while coasting or engine braking.... Popped the hood later while running, had exhaust leaks all over both manifolds. She was running a little rich too, so my guess is the exhaust was hot enough and leaked bad enough to actually cause a little combustion in the exhaust
Exhaust leaks are the number one cause for popping out the pipe..
 

coachdtierney54

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Normally I downshift going down the mountain to try and save my front brakes, but it pops more frequently and louder than not downshifting. I'm looking for the pic of my exhaust now. I'll post it soon.

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coachdtierney54

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Header into a 4ft straight pipe, then into muffler, then into turndown. That's it...
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Honky Kong jr

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Header into a 4ft straight pipe, then into muffler, then into turndown. That's it...
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Is that shadow or soot in the first pic?
 

Honky Kong jr

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@Cuba I agree but I can't touch it to prove it.
 

coachdtierney54

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I'll check tomorrow and let you know

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coachdtierney54

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Now that I think about it, the popping sounds like it is behind me, so it makes sense that it might be the connection between the pipe an muffler.

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Honky Kong jr

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Get rid of them u clamps and put some stainless band clamps on there they seal great and don't crush the pipe.
 

theblindchicken

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Aren't you supposed to have any adapters set so they flow into the next pipe like a funnel. If its the other way around, they'll leak.
 

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