XkrazyAsianX

iTrader: (5)

Well, it's a misfire in the 4th cylinder. I know my spark plugs are due, could that be the problem? Anything else that i should worry about? Any input's appreciated.

Car: 04 WRX
Mods: vf34, sti injectors, walbro fuel pump, perrin crank pulley, borla headers, helix up and down pipes (catless), borla hush.

subie OCD

iTrader: (11)

How many miles? I had a misfire code (cylinder 4? dont remember) along with 2 other codes before I had my CEL fixes. This was about ~ 35K miles. My mods are catless up, highflow TBE, IC hoses and ecutek.

A friend told me it was due to the o2 sensors reading to much fuel/too hot...?? Maybe someone can explain it better. I dont know...but now that I did the 2.2k ohm 1/2 watt resistor for the uppipe and mechanical fix for the rear o2 , none of the CEL's have come back. Im at 52K miles now.

Do you have a light flyheel?

XkrazyAsianX

iTrader: (5)

i just hit 40k recently, i have the mechanicl o2 sensor fix for the dp, but nothing for the up, maybe i should do that ><

Onizuka

iTrader: (17)

I would ask someone about fuel rails - I remember someone saying something about one of the cylinders being the weakest, hence, the need for fuel rails.

WREXNFX

iTrader: (3)

you dont need a O2 fix for the up side you will screw up your fuel mixture
running a VF34 your plugs are going to go alot quicker id replace the plugs and go from there see if it happens again.

DetailAddict

iTrader: (52)

i had something similar. just replaced the plugs, cleared CEL, and never came back. good luck!

lovesmysuby04

iTrader: (4)

Start with the plugs, of course one step colder than stock. Report back if the problem is still there. Check out www.clubplug.net

qwk_wrx

iTrader: (4)

my guess is plugs also, so no lightweight flywheel then? because i think they can cause a misfire code.