Back Firing

[240sxHitman]

I was wonder what would cause back firing. i have a CAI,Stock headers and 3" HKS hi powered exhaust. this back firing just started recently and i had the exhaust on for awhile. some one said its my timing and another said the fuel/air mixture. what exactly could it be

[nissilvat]

u know i got the same problem, i have a crack in my stock header though, but when i accelerate, then let off the gas, it make s loud pop noise, not like a shotgun blast, more like a cap gun , but it makes this noise every time

[ddgsxr504]

Your backfiring comes from rich airfuel ratio and your 3" exhaust which cause less back pressure. I have the same problem and I have a 3" Apexi N1 exhaust, Injen CAI and Hotshot header. You may also have a bad O2 sensor!

[crzycav86]

Backfire is perfectly normal on any motor.

It's just that you don't hear it with the stock exhaust.

[c-rad]

lol, backfiring is really when the combustion process exits the intake ports and out the intake manifold.

[PandaS14]

yea, mine backfires too.

One of the reasons it does this too, is that the stock a/f ratios are relatively rich. And like said earlier, you hear it once you fee up the exhaust flow. Mine does it more when the engine is cold too. This is because startup enrichments for your engine when it's cold are richer than when it's warmed up. Some of you guys might have noticed this too.

As long as they aren't like shotgut blasts, there's most likely nothing wrong.

[sileightysomeday]

mine does it, and i dig it. it makes me smile.. hehe.