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Decel Backfire

dmonic1

By dmonic1,
in Four Door Family & Wagoneers

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dmonic1 Community Regular

dmonic1

Posted
Posted

my car has all of a sudden started to backfire or pop while decelerating. it normally happens while just cruising on the speed limit or so and when i back off for reasons like traffic or coming up to a corner the car will occasionaly give a lttle pop out the exhaust. its nothing loud like the old key bangers i used to do to scare the shit out of pedestrians in the sigma but i was just wondering why it would just start happenening. i fitted the new turbo and front mount a month or so ago so the only reason i can think of is because its so cold at the moment. i adjusted the blow of valve so that it is at its hardest setting but it is a plumb back anyway.

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bluesky4me Community Regular

bluesky4me

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Posted

Mine does the same thing..more so when its in triptronic mode..mine has a big exhaust and Blow off.From what I know it does this as a result of running rich and the poping is unburnt fuel..it can also be a result of a worn out O2 sensor I believe. I dont think it is a major cause for concern...sounds cool...but..the thought of using more fuel than is nessesary..aint a good one.

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Xmetal Mentor

Xmetal

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Posted

All it would be is unburnt fuel going out the exhaust, mine used to do it all the time particularly if I go up it then threw out the anchors straight away.

Gut your cat converter and watch for the flames....and the police. :P

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dmonic1 Community Regular

dmonic1

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yeah i was thinking i might have a small air / vacume leak somewhere as when i boost it i get a little whistle from somewhere other than the normal boost noise. i already have a decat pipe and i have been told that i pop flames on up changes when it tickles the limiter.

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GoldZilla Grand Master

GoldZilla

Posted
Posted

It's just un-burnt fuel, and it shouldn't be an issue. When you back off the accelerator, some of that extra fuel might still go through the engine, and when it reaches the exhaust the high temperatures cause small explosions in the exhaust manifold and dump pipes, etc.

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