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


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If the tuner said a coil has decided to break down, get him to tell you which one.
If my memory serves me correctly a local tuner told me that he could not tell me which coil is faulty only that I have a faulty coil(s).

did the tape up last night and the 4000-5000 popping has gone so far will try high boost after work when the roads dry up hopefuly! but boost comes on strong and not pop in standard boost so far! hopefuly will get my safc2 tuned tonight if the weather holds up!

and see if that makes a difference to the flat spot also!......can't wait!

A thread started by Benm made me try taping the coils it was worth a try

http://www.skylinesaustralia.com/forums/sh...ed=1#post963082

You do realise you have made a reference to the very same thread you posted in...

taped up coils..... lol

 I wonder how long that will last for :P Good on ya KIWI ingenuity!

Good question. I think the loom for the coils is wrapped in electrical tape, and that has help up since the car came out of the factory. So as long as you use good quality tape it should be OK I guess....

Guest Slide
You do realise you have made a reference to the very same thread you posted in...

 

 

Good question. I think the loom for the coils is wrapped in electrical tape, and that has help up since the car came out of the factory. So as long as you use good quality tape it should be OK I guess....

yeah

i meant to do on other thread

i browse over lots

Very useful info from all you guys/girls on SAU

i have the same problem ... with my R34 GT-t

NGK LASER IRIDIUM IR regap to 0.6 mm then its gone ... but still 0.6 is really small gap for std boost

i'v changed them to new NGK IRIDIUM IX gap them to 0.8 mm ... still have some mis .. but better then befor ....

at idle i have some misfire ...

when i reach 5000 - 5500 rev .. i have about 2-3 pops . and thats it

but i feel like .. am losing power ..?! .. checked my coils .. they look like new ones .. no crack on them ..

i'll regap them to 0.7 see what happen ..

the car have done 49,000 km now ...

i think .. am going for new split fire .. for about 500 -450 AUD .. about 1200 - 1400 DH in DUBAI .. not really sure

but they are made in tiwan or thiland i think ...

is there anything wrong with those tiwan coils .. ?? they are new .. !!

just dont want to spend money for nothin ..!!

  • 1 month later...
taped up coils..... lol

I wonder how long that will last for :) Good on ya KIWI ingenuity!

Well I now have an answer for this question :P

about a week

I have also posted in this thread, my current status...

I purchased 6 coils from intersate only to find they were all cracked too! :P In my moment of frustration, I grabbed my soldering iron, and the lid of a can of black spray paint :)

I melted plastic from the lid, over the cracks on my coils. I melted heaps to fill those suckers in..... (NOTE: At this point, i wasn't try to fix the problem, but the cracks had p!ssed me off, and I have a very bad temper... So it was do this, or smash the coils into little tiny pieces with a sledge hammer)

Anyhow, back on track, I melted heaps of plastic over all 6 of my original coils (only 4 were cracked). I put them back on, still pesemistic at this stage.... (I also slapped on an R32 wastegate actuator the same day, and it was misfiring at 4500 - 5500 rpm at 10psi). I started the car, and it idled just fine... actually smoother than before....

I took it for a drive, and once adequatly warm (15 mins of driving). and also in an appropriate speed zone, I let it redline in 2nd gear... nothing... No hessitation, no misfire, just smooth linear power to 7000rpm! (NOTE: I also have a SAFC2 to sort my A:F ratios)

So now I'm thinking plastic welding sounds like a good option for people with cracked coils. (dunno why I didn't think of this earlier).

It's still early stages yet (4 days so far), and I dont expect my coils to hold up. Only because melting plastic with a soldering iron like I did, only melted the new plastic I put on. The plastic on the coils was still cold, so I dont think the 2 fused together properly. SO... I think that with time, the plastic I melted on will un-stick from the coils.

I'll report back in a few weeks though, and let people know how it goes. Has any1 had quotes for plastic welding before, and if so, can they approximate what 6 coils will cost to get welded based on that?

Zahos

  • 3 weeks later...

Have found cracks under the bracket that holds the coil pack bolted in and I will try to fill the gap between it and the coil pack with araldite tomorrow as taping was only a 50% improvment to missfire. Will post how I go tomorrow night.

Just a quick reply to give results of my coils since last post, was getting misfire at hi revs' pulled all coils out covered the yellow end wit aroldite, like other reports said to do, also found a hair line crack in one coil, cleaned it up aroldited that aswell then used electrical tape over that, problem fixed!!! wooohooo!

i haven't encountered this problem yet.. but i would imagine that if you were looking at this for a long term fix that a gasket silcone or maybe areldite would work best at lasting the test of time.

just a thought :confused:

I used permatex high temp gasket maker on my coils ,which I pushed between the coil and the bracket that bolts go through to hold them in place. I also covered any other sus looking spot as well.

By pushing silicone through from top to bottom of gap in coil/bracket with a ruler or paint scraper until it oozes out then smear it out even I got my best results.

Note; I could see the burn marks on the coils so it was rather easy to see the problem,if you can't see them try it and see if it solves the prob. it did for me. :bananaman

  • 3 months later...
  • 2 weeks later...
a pic would be cool!

The photo quality couldn't get much worse, but anyway...

Cracked coil:

coils3.jpg

Burn mark:

coils4.jpg

Araldite:

coils1.jpg

Gap - fill all the way around from both sides:

coils2.jpg

Gasket maker:

coil5.jpg

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