What's Causing My Missfire?

[browneye91]

Hey guys

Iv had my r33 s2 for bout 6 months and for the first 4 months it ran sweet. But all of a sudden it developed a miss so the first thing I did was turn my boost down to stock levels as it was at 10psi. This didn't stop the miss, oh and I had just recently done a service on it and changed the plugs and gapped them to .7.

Over a few weeks it got worse so I found some second hand coilpacks from on here and the guy who had them said they worked fine at 14 psi for him.

Why is it that now after a few weeks of having them in it is still missing?The miss was not as bad when I first put the coils in and it would take more boost around 10psi again but it has died off and has started to miss like bitch again. I'm planning on getting some yellow jackets or spitfires in a few weeks but if you guys have any clue as to what else it could be any help would be awsome! My list of mods are

3" exhaust

Fmic

Blitz dual sbc

Apexi afc neo

Pod filter

Pleeeze helps me I don't like having no powers!! =[

=]

[DVS JEZ]

See if u can borrow an ignitor from a mate, thats if s2 use an ignitor. Otherwise wait till u get the split fires and see if that fixes it

[JKR-32]

S2 don't have an ignitor. Does it miss when idling? If so, you should be able to narrow down which cylinder is missing by unplugging each coil pack individually in turn. Then when you have found the one that didn't worsen the idle from unplugging it, you can swap it with a coil pack from a different cylinder to see it the problem moves with it. If the problem moves with it, Bingo! You've solve the mystery. If the problem remains on the same cylinder then it means that something else is the issue like possible injector problem or coil pack loom etc....

[zoidbergmerc]

What fuel are you using?

[R31Nismoid]

I'd be the plugs are fouled and/or the wrong type

[browneye91]

It does miss a little on idle but it is bad under load. I use Bp ultimate. The plugs are coming up 5000 ks and can't remember what plugs I'm using think they bcpre6 or something like that

[yye-33w]

Hey mate,

I'd make sure you have the platinum or similar spark plugs which are about $23 ea first.

I'm having a similar problem to you though. Although mine happens under load not on idle, idles fine. you can take your coils out and get some good insulation electrical tape (not cheap shit) and tape 3 or 4 layers over the stem of the coil as they earth out somehow. I did this with mine but its still missing under load but not as bad. I advise to get someone you know who has good coils and try them in your car. Then you can eliminate the coils. As far as i know the stem earths out under load aswell as the maind part breaks down. I think mine are breaking down at the main part. Im getting some coils off a guy in QLD and i hope it fixes the problem..

If not it could be the coil loom. Its just a process of elimination which is easy as you can do it your self

Also what ECU are you running? stock?

I'm running a Wolf 3D ver 4 which isnt the best but i know it has been tuned to 310HP when i first got the car so the computer isnt the issue with mine.

Hope this helps dude.

Kier.

Edited February 17, 2011 by yye-33w

[SECURITY]

Firstly, you don't insulate the stem. It's the actual coil pack unit that earths out.

Try some known working packs and see how you go

[erderr]

+1 for plugs

[browneye91]

Yeah mine happens under load as well just on idle it skips every now and then so no miss on idle. Yeah got stock ecu i have added front mount and recirc blow off valve since getting the car so it could probably do with some adjusting on the afc neo but I will go over things on Sunday and see how things look permitting its not bloody hot!! What plugs do you recommend using kier?? Cheers for the feedback fellas

[SECURITY]

if its not plugs then its your coil packs. ask a local perth SAU member if you can swap over splitfire coil packs (make sure its a series 2 as well) to test your problem.

[browneye91]

Yeah I was gonna check with my neighbor as I'm pretty sure he has splitfires I hope it's the coils or plugs thanks again guys!