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Ok so over the weekend i installed a FMIC. and had a few flat spots, ect, trimed up the SAFC II and redid the timing, and all good, no problems, car ran fine.

I got a flat batery, i forgot to turn my lights off, so the computer reset itself. Eitherway, after a charge the batery went back in and the car ran fine, but i did not thrash it as recomended after an ECU reset, as i was driving on the highway with my family.

So the car just ran, and seamed fine. I gave the car a gut full a few times on the highway and no problems no missing, nothing.

So this morning, going to work, gave the car a boot full, and i got missing at 4500rpm to 5500rpm, and then nothing and pulled fine all the way to 7000rpm, i made sure that it wasn't a once off, and definatly not. Seamed to happen constantly. Tried to fiddle with the SAFC II, but it all seamed thesame.

SO i already have the sparks set to.8mm and retaped up. I tried to do my idle and timing but, for some reason i can not get the idle to drop below 900 rpm with the TP off as the manual sugests, which means a littel unsure about timing seting.

The car is runing 8-9 pis boost, FMIC, 3' exhaust turbo back, hks pod and intake. New fuel pump, new 02 sensor and ecu temp sensor. and Adjustable fuel pressure reg ect.

The symptoms seams a lot worse when the car is cold, and only occur under 100% throtle. If i am off the throtle a bit 80% it does not miss. Once above 5500rpm no missing, pulls fine all the way to the top.

The only thing i am thinking of is the coils and plugs again and the computer reset. I am also goignto chech for leaks and clean my AAC valve.

Help with any advice, i realy love my car, but am becoming a little dishartened about all the little nigles that happen once you start to play with it.

HELP, please anyone.

ALSO>>>>>>>> how do i check for vacume leaks and exhaust leaks, best way that is.

Edited by WogsRus

my Air Flow Meter is the original one 72K on the clock. I had cleaned it ect some time ago, and it looks very good.

I still have standard coils and coperhead plugs gapped to .8mm, and i am preadty sure it's my coils, i rad the big post after i did some more searching. I i am going to get some hi grade hi temp silicon and silicon up the coils to see if teh problem goes away. if not, something else is amiss.

yeah i had already previously taped up my coils for luck, just to make sure, but the problem is back, it missed when i first got the car, now it does it again.

So tonight i am goign to get some silicon and silicon the bastards up.

Does anyone know if this trick would work on a series 2 without an igniter pack.

http://gdz1la.kol.co.nz/prod01.htm

Is it an R34? I had the same issue and tried regapping plugs and taping coils, in the end I had to get splitfires to solve the problem. About the cheapest you can get them is $550~ delivered from Japan.

I'm sure if all the R34 owners on here that've upgraded to splitfires pooled their old coilpacks we'd have about 50 that still worked fine... it's just a bitch taking them in and out to find out which are the faulty ones.

unfortunalty mate shes an R33, and i have my cover off so it's preaty easy. I am looking at doing a wasted spark setup, but at the moment, no money, need a temporary fix as i drive the car every day.

SO i'm going to silicon them up, well and see how it goes from there.

.

unfortunalty mate shes an R33, and i have my cover off so it's preaty easy. I am looking at doing a wasted spark setup, but at the moment, no money, need a temporary fix as i drive the car every day.

SO i'm going to silicon them up, well and see how it goes from there.

make sure you check for cracks between the coil packs and the rubber bit that covers the spark plug.

Out of my 6 coils i found a crack in 2 of them, and thats where i found all the cracks, good luck

Well did it all last night, used heaps of silicone, no plastic showing, non what so ever, and still misfire. only at 4500 and 5500 rpm.

ONLY small though. I think it might be ritch and retard, as when cold at 6 am the car is boosting to 10psi and when warm only to 8.5 psi.

And when warm the car runs fine, no probs.

I am going to setup a wasted spark ignition system, went to see the boys at Automotive solutions, and boy are they handy, got all the peaces priced with custom cut lenght leads, a total of $150 but i still need a cheep igniter.

DAM IT.

WHAT ELSE CAN I TRY???

i will regap to .7mm if missfire disapears, definatly coils, if not R&R

Edited by WogsRus

it miht be a loose connector on the ptu (little black box on top of com covers at rear that sends power to the coils)

at that rpm you might be getting a harmonic that is causing a loose contact to dislodge in the ptu

worth a try...

nope not tuned properly yet, going in on tusday. The weird thing is i do not understand why missfire ONLY when cold.

It's hard to dignose as i can only show somone when it DAM cold. LOL

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