Missfire Boost@4500-5500 RPM - The Answer! (for me at least!)

[cerci]

hey guys im havin the same prob

any1 in syd who is good at doing this plz pm me so u can fix the prob for me

ofcourse u will be making some money

i dont wanna here "its so easy u do it"

remeber, im paying you

[damono]

Im having a similar problem i think, although im not getting any misfiring i think, just hesitation. Ive been told so many different things that it is. Im gunna try and take out the coilpacks this weekend and give it a go. I had it on the dyno and it showed a BIG drop in power (about 40rwhp).

It pulls hard then when it hits about 4000rpm it hesitates and you can feel a big loss in power. If I run about 0.65bar its fine, Worse if the boost is set higher. Is this the problem people are getting. My mods are 3" turbo back exhaust, hybrid FMIC, manual boost controller and hks air filter. Any ideas?

[ZOR]

i'm having similar problems just up'd the boost and with new exhaust and boost controller and now. spluttering and running crap. changed all the coils and still the same problem. i just put in a power fc and sending it 2 the dyno next week for tuning i think it also may be over fueling which might be the problem.

Edited October 11, 2005 by zorma3nz

[WLD747]

Hey Guys,

Ive got a r33 series 1 & i have replaced my coils with rb20 coils. The only difference i could visually see was that inside the boot to the coil my series 1 would only have a stuffed up spring. In the rb20 coil it had a little pallet or something just at the tip of the spring (maybe a spark conductor of some sort). I have put these rb20 coils in and have gained a little bit of power and no more misfire. I also did spray the coils in high temp spray before putting it into the car as i did see arc marks on the coil, but works great.

Does anyone know what that pallet thing is, i didnt get a chance to take a photo.

cheers

AK

[noise]

The worst part about this thread is that no one suggests using cheap copper plugs instead of iridiums, which for many people would fix the missfire problems.

Hey I only just found out, dont look at me

worked a treat in my GTT.

[JimX]

How do you test the coils with an ohm meter? I had misfiring problems at above 6000rpm. I tried patching up the coils with silicon but it didn't make any difference. My mechanic had said that 2 coils were drawing too much current and causing the misfire, but I forgot to ask him how he tested them.

I have since replaced the whole lot with Splitfires (they are quite cheap from Nengun and Perfect Run at the moment if anyone's interested) which has fixed the problem, but I'm wondering if I can now check the coils with an ohm meter to see which the duds are.

[T04GTR]

this used to always happen to me on the drive down to wakfield.

the cooler was nice and cooled.

[FATAZZ]

anyone else in western sydney thats already taped up/arreldite'd

their coils on a rb20det that wouldnt mind lending me a hand to fix mine too please?

beer supplied

[ruffryder]

Hey guys i dont know much, but i think i might have the same problem that has cost me over 1gran of bs n alot of headaches. can anyone confirm if this is it, here is my post details:

"im currently running 11psi boost on my r32.

when i hammer the car, the boost, regardless of what gear i am on, will quickly hit 11psi on the boost gauge.

... but as the revs slowly creep past around the 4000-5000 rpm mark, the boost starts to slowly fall, and i can hear 'popping' noises from my exhaust.

from this point onwards, torque is lost and as the revs go up, car feels jerky n no torque.

just hear popping noises n car is kinda 'jerky' with the pops.

i thought it was the fuel pump, but i just got an 040 installed and still the problem remains"

cheers guys

[driftmeister]

Hi Guys

I seem to have the same problem when I change to HKS Iridiums 7 heat range after a couple of weeks then I started driving it like I stole it. The misfire appeared like waht you guys mentions. My ride s a R34 GTT. Im interested to try out the araldite but am confuse by their range thats available. Can someone show me which type are u all using? I have a link below.

http://www.adhesivehelp.com/vantico.html

Thanks in advance.

Hope to fix this problem so that I can enjoy driving again...Cheers!

[Zahos]

when you get to your hardware store, you will not be faced with that selection...

Any of the epoxy's that bonds to plastic should do fine.

Make sure it is a 2 part mix.

[sl33py]

Last night, after a hot 30 minute run in fairly warm Canberra evening heat, my car did this. When I floored it: it's fine until about 4.5k, but from then on until I hit 6.5-7k, the engine seems to cut in and out very quickly maybe 5-6 times a second. I think it is misfiring, it sounds like it's backfiring too, but I expect that is only a side effect from the fact that it is misfiring.

I tried to recreate it again this morning, but to no avail, winding out 2nd to 7k, I couldn't do it (after 10 minutes moderate driving to warm it up enough to put that kinda stress on the engine). I'm gonna see if it only does it when the engine is *really* warmed up again, like it was last night. Is this pattern typical of the problem? Is it worse for everyone when the engine is hot? And less obvious when cool?

[sl33py]

Looks like my misfire wasn't the coils. Changed the plugs in my 96 GTS-T S2 to NGK BKR5ES-11 and took her for a run. After temp got between 1/3-1/2 (what I consider warm) I did 5 or 6 runs to very near redline (6.5k). No misfires. Then on the 7th run I noticed the engine temp was up to 2/3s and rising, so I backed off and pulled over. Temp went back to normal. During the idling period, I only got 2 very slight misfires in about 2.5 minutes. I figure if the engine temperature got as high as it did, I'm driving it harder than I should, and since I didn't encounter any misfiring at WOT during that period, I consider my problem fixed. I suppose if I was to do something to the car to improve the cooling system and the temperature stayed acceptable, I would continue to run it hard and see what happened, but since I'm not modding *just* yet, I'm satisfied!

[sl33py]

I was wrong. Did the test where u look at the engine in the dark with the cover off so you can see the coilpacks. Mine are FAAAAAARRRRKED! lol

I'm arcing from packs very badly 1, 3, 6 (about once or twice a second from each!) and after that I stopped looking cos I was so happy to see an obvious reason/fault. I'm ordering Splitfires from a site for very cheap (sub 600). Once I've received them, I'll post the site here, as I don't want them inundated with orders before mine ship (esp at XMas time)

MAN I can't wait to rip those pieces of #(*# out of the car. Even my mechanic and the dealer said they were ok.

Taking the cover off and watching the packs dark test works!!! "DUU it!" as they say in Starsky and Hutch. Note: I couldn't see the arc from the front, only from the side and when sticking my head in so I could see right down into the depths of the coilpack area. I assume I saw arcing cos not all the packs were flashing regularly, and only some of them were doing the flash I saw.

[sl33py]

Splitfires for $550 delivered as of 20/12/05 = www.perfectrun.com.au

Mine are in Redfern on the 19th after being dispatched in Japan on the 17th!

[sl33py]

MISFIRE GONE! car idles better, runs slightly smoother overall. Go the splitfires And damn do perfectrun deliver quickly! Even during the Christmas mail-busy season

[soon2b33]

i recently developed the missfire at exactly 4500 rpm so i new exactly where to look i used a heat resistant insulator sealant, and then went sick with the tape.

Car goes like a rocket! im so impressed i think its been getting worse but i just havent noticed til performance plummeted last night.

Thanks to the guy who came up with this, you're a legend!

Is this solution meant to last, or is it only extremely temporary?

[Fixxxer]

I had a nasty miss, not so much in hot weather but really bad missfiring especially at night, anything over 8psi and anything over 4000rpm. RB20DET, intercooler, 12psi, R33 turbo. I finally got around to changing the spark plugs and found that the "Iri-top8" plugs that were in the car looked like they had done 2,000,000km, the electrode had been eaten away to the point that they were almost 1.1mmgap, rather than 0.8mm..... so much for the guy saying my car had been serviced recently. The coils I looked at, none seemed to have a hairline crack, but all 6 of them had fairly major discolouration due to arcing.... problem found.

Solution, new NGK copper plugs @ 0.8mm, NO tapeing/glueing/insulating of the coils, just put them back in with the new plugs and walaaaaah! the miss has completely gone (for now, hopefully forever). Ohhh and a tip for all, always use anti-seize stuff on the spark plugs because my plugs were almost welded to the head.

I figure that the first problem was the iridium plugs, maybe needing more energy to spark and secondly the plugs were waaaay worn to the point the were approx 1.0-1.1mm gap, making it even harder to spark. Hence the easiest route for spark was not to arc across the plug, but rather arc to the head, causing the discolouration/melting of the coil. With proper new copper 0.8mm gap plugs the car drives so much better.... now i just need to put it on the dyno and see what the AFR's are doing.

Fixxxer

Edited December 28, 2005 by Fixxxer

[b2barker]

I have had my R33 for 3.5 years and this missing over 4500rpm has got progressively worse. I took out the coil packs over Chrissy and all 6 had the hairline cracks. Applied the araldite, allowed to dry and refitted and...

No miss, perfectly smooth to redline. I am loving my car again, and I wondering why I didn't extract the digit earlier. $13 and an hours effort and it's all good. Now I am ready for manual boost controller and probably AFC fitting.

Very happy and many thanks to the previous posters of what is IMHO the most helpful thread on SAU.

[mid life crisis]

gday all

ive had the same miss around 4000 to 5000 under load . so decided to bite the bullit and change the plugs went for copper core type and checked the coils out at the same time .while i did not find any obvious cracks there was signs of arking.wrapped the coils in quality tape thru the plugs in and wallaaaa no more miss car goes like a rocket 13 bucks for plugs couple bucks for tape and a hrs work prob solved . well done to the guys that fig this one out

mid life crisis