Rb26 Misfiring On Boost

[Turbz_13]

I know this could be 1 of 1000 things.

but i was wondering if someone could point me in the right directions as to sort this issue!

Basically, the car has not really been driven for a long time. Finally iv got the car back on the road. changed plugs and oil and filter. Took it for a drive and it was running fine. Til i started to roll on the boost, it was as if it was ignition cutting(like on the rev limiter would. just my description of the issue)and when i backed off it started to back fire big, i guess burning the unburnt fuel.

im gonna start with the igniter module, check a few sensors and the grounding.

i was told it may possible be a dud injector leaking internally into the rail then into that cylinder once backed off??? i didnt really understand the description properly that i was given on this

any help would be greatly appreciated!! cheers guys

[r32-25t]

Coils

[The Dan]

Why was it off the road for a long time? What was done to it?

[Turbz_13]

coils are around 35g km's old and are split fires. i will check them but iv been told they should be fine. but ill still check of tracking marks etc...

the car was off the road, 1, i lost my license 2, i blew a stock intercooler hose and was waiting for replacement and 3, the clutch was starting to slip once it had warmed up so i wasnt using it. No mods or anything

[Nee-san]

Very Similar situation,

Car was offroad for a long period (although regularly run) and now starts to splutter and misfire at approximately 4500RPM (boost) Have changed plugs and check the splitfires (which are quite new around 10000km old)

Any suggestions ?

[DVS JEZ]

Did u gap the plugs down around .8mm?

Do the simple things like fuel filter etc too

[SiR_RB]

Coilpack loom ?

[Rolls]

Are the plugs old? Could have been sitting in oil/fuel/water all that time for whatever reason fouling them. Though if it was oil or water you probably have bigger issues, possible a very very small leak could have covered them in that time though. Also if it was very hard to start first time you could have fouled them running rich.

Definitely sounds like a spark issue, I'd look at new properly gapped (0.8mm) plugs first, if the coils are new this shouldn't be an issue, next is is there water in the valley? condensation on any of the ignition components?

edit: If the intercooler hose blew it probably ran rich as shit fouling the plugs. The other thing is are you sure you fixed it properly? As a boost leak causes similar symptoms, stalling, missing, blowing dickloads of black smoke when going on to boost.

Edited January 17, 2011 by Rolls

[DAN00H]

spark and therefore coilpacks/ loom/ plugs would be my guess, but also check your AFM plug connections

[Beer Baron]

since you just changed the spark plugs and now have this issue that's where I'd be looking. check they are the correct type and heat range and that they are gapped appropriately for your set-up.

[Nee-san]

Hey guys, Sorry to drag this back up,

Have checked the following and it is still blowing out spark albeit at around 5500 now rather then 4500

Splitfires

Ignitor

plugs, changed AND gapped

removed and cleaned AFM and tightened all plugs (voltages all read correct)

Removed inlet piping and re-tightened hose clamps (helped somewhat) still wont run more then 0.5 bar though.

What about gaskets on the turbo compressor outlets to twin turbo pipe, these two are a bit suspect.

any ideas boys ?

[The Dan]

fuel flow/pressure

dodgey fuel pump or blocked fuel filter

[Rolls]

its not running sub 10:1 rich is it? cause you can get a rich misfire below that.

[Nee-san]

I can check this but if i was having pressure/flow issues would it still blow a metric f**kton of black smoke once it hits boost ?

[Rolls]

unlikely

[Nee-san]

Would a f**ked gasket Cause this ?>

Cooler leak ?

[DVS JEZ]

What ecu? Do u have access to a dyno. As above if its too rich it will cause a rich misfire.

[Nee-san]

Power FC, Standard AFM's yeah i can get it run up on the dyno but im getting it tuned next month so i dont really want to send it their twice.

[Rolls]

its $40 to get it checked out for a single run.

edit: missed that it wont boost above 0.5bar, it most certainly is a boost leak causing it to run sub 10:1

Edited January 24, 2011 by Rolls

[Nee-san]

Yeah, money is no problem is just the booking in and waiting etc I suppose ill have to if i cant track it down.

No one thinks gasket ?