Backfiring problems...

[BLKCIVICPN0I]

I have a 00 JDM b18c swap in my 00 Civic with bolt ons and on a PCT ECU.. My problem is that when i'm revving high around 4000 rpm nd up, my car starts to backfire like crazy. When I'm on 1st nd hitting 4000 rpms it'll start backfiring den when i shift to 2nd it'll continue. Has this ever happened to anybody? or does anyone know what can be wrong? Some ppol say it could be my timing, exhaust ( I have a mugen 4-1 header w/ a 2.5" inlet connected to stock pipings), distributor cap & rotor... Any help is appreciated...

 

[E_SolSi]

got a cat?

 

[BLKCIVICPN0I]

i have a stock cat...

 

[CRX_B16B]

I would check timing. does it knock?

 

[BLKCIVICPN0I]

no

 

[hybrid_b18]

yea my hatch used to be really bad wen i had my custom 2.5" exhaust no cat, but when i went back to the ls exhaust it stoped a little. so i dunno. i didnt kno timing would cause you to back fire. what to advanced or retarded? let me kno if you find out anything.

 

[cws13]

When it's hot or cold and are you running rich?

 

[driverunknown]

check timing

 

[cws13]

True, sounds like spark knock- but that wouldn't backfire.

 

[hybrid_b18]

I MAY BE RUNNIN A LITTLE RICH

 

[hybrid_b18]

sorry mang i dont wanna be buttin in on your thread, but im havein the same problem. diffrent engine

 

[E_SolSi]

running rich is a given
gotta figure out why....

bad plugs (fuel not burning fully)
timing off
no cat / bad cat
ECU just dumping way too much fuel in (most chipped ECUs run stupidly rich)

 

[highperboi]

why would not having a cat cause backfire?

 

[E_SolSi]

because the cat is there to burn up unburnt fuel before it makes it to the air
but if you are running retardedly rich it cant burn it all

 

[B16ASilverhonda]

Originally posted by E_SolSi@Feb 25 2004, 12:04 AM
because the cat is there to burn up unburnt fuel before it makes it to the air
but if you are running retardedly rich it cant burn it all

wrong cat is there to turn hydrocarbons into carbon dioxide and water. PCV valve carries blow by gases from the crankcase back into the intake system for re-entry into the combustion chamber. Maybe clogged PCV valve?

Defently Check:

Timing
PCV Valve
Plugs (NGK's ONLY or Denso's)
Spark (Wires, Cap, Rotor, Etc)

If you back fire too much you can bend an exhaust valve, think about it when your backfiring air is entering the exhaust system. so be careful