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Car Back Firing?

ginger

By ginger,
in Engines & Forced Induction

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342Four Grand Master

342Four

Posted
Posted
If its popping on decelleration or gear changes, whats the cause of that? the BOV?

see what i wrote:

thats called overrun

thats different to backfiring cause the engine is at high-ish revs, but there is no real load on the engine, and so it revs without using the accelerator

there is an excess of fuel in the burnt mixture because of the closed throttle, and when it hit the cat converter it mixes with a bit of oxygen and self ignites

thus the pop/gurgle/burping noise

backfiring is like a full on ignition of fuel/air mixture partially in the engine and in the exhaust - thats why its loud and bad for your engine

R33Turbo Proficient

R33Turbo

Posted
Posted (edited)

so the so called overrun ain't bad for ur engine? cuz i have that exact described issue "overrun" like QUITE OFTEN during driving which i really think the BOV is the cause for cuz other than that i have just a catback exhaust (with stock cat convertor) and it overruns very often. One more thing, it occurs at low RPM like around 2-3k rpm ... stilll is overrun?

BTW: sorry to borrow the n/a thread like dis as wat i said about BOV has nothing to do with the thread starters issue obviously

Edited by R33Turbo
342Four Grand Master

342Four

Posted
Posted

hmm, maybe your issue is more over fueling and not burning all of the fuel properly

i would look at maybe getting the Oxygen sensor changed, getting the timing checked, really, just checking out the fuel delivery system to make sure it is all good and that all sensors are working properly..

r33cruiser Grand Master

r33cruiser

Posted
Posted

absolutely right r33turbo. vta bov's do make the car backfire...purely because thats what they do. when i switch back to plumb back....all my pops are solved...but not as aggressive to drive.

r33cruiser Grand Master

r33cruiser

Posted
Posted (edited)

my vta bov has a larger diameter valve. hence more air can get out. with it on, i chirp 3rd.

its gives better response imo

stock bov does shit all. probably leaks etc

Edited by r33cruiser
  • 3 weeks later...
MicR33 Apprentice

MicR33

Posted
Posted

Yeh mine back fires sometimes also, i got a new exhuast system put on in december last year, and beginging of feb the hi-flow cat was stuffed, it rattled and made my exhuast sound like sh*t, the guy asked me was my car back fireing i said sometimes, he replaced it under warranty no worries, but was prob cause car was back fireing maybe, to what u guys have been saying, just hope it doesnt stuff up again. What would i have to do to fix the issue.

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