Rb25det Missfiring

[WPN-O33]

Hey guys my car is missfiring from idle & all through the rev range, no smoke coming from the exhaust so no engine failure i'm hoping.

Yesterday this happened & after a couple of start ups & holding the revs at around 4000rpm the missfiring went away & it drove home fine on the highway & for around an hour. This morning when i started her up she is coughing up the same but no sign of going away this time. It is pretty much running on 4 cylinders or 5 maybe i'm no mechanic.

I thought it may have been a bad bit of fuel but no such luck it seems, i'm thinking it maybe my Splitfire coilpacks, they've been on the car for around 4years now, car was last tuned in august last year & has run great as normal until just now.

I will be taking it to my tuner hopefully this week & getting it sorted but i thought i'd ask some of you gurus & get an idea what it maybe.

These are my mods

Highflow turbo

Injectors

Coilpacks

Link ECU

Platinum Plugs

& All the usual support gear.

Thanks guys

[The Dan]

take off the coil pack cover and replace all the other parts so the car will run. Carefully remove the coil pack plugs one by one and plug it back in. The one that doesn't change is the cylinder that is misfiring. Now you've done step one, you need to determine whether it's cylinder, spark or injector.

[45ULT]

if u say there's no smoke coming from the exhaust then i'd start with the missing cylinder having no fuel. cause if it was misfiring but the injector for that cylinder was still working then it would have unburnt fuel in the exhaust and make black smoke. easiest way: determine which cylinder/s are dead check for spark condition of plug and coilpack, check for injector working by putting a screwdriver onto injector and putting your ear on it and listen for it pulsing. sometimes disconnecting the injector will make it run better but this is only if the injector is leaking too much fuel. failing that try a good old compression test