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

[Booya]

Well found that my prob was getting worse with it misfiring all the time now. Drove into town on Sat got home and left the car for about 3 hours. Tried to start it up again and the battery was flat...............

And i was reading someones post about how his battery was suuffecient enough to run the coil packs and cause misfiring. Well gues what its true. Replaced the battery and she was running smooth again.

I still found that it misfired above 4 every now and then, didnt always happen. Occured specially in 2nd.

This wekeend going to try the replace and regap the sparks and see if it helps, otherwise ill replace the coil packs.

[driftmeister]

Hi Booya

It was me mentioning about the battery change. Anyway i am going to upgrade the battery to a bigger type (NS 60 intead of 40) than the originals. I only hv few misfire for the past one week & that happens whe the audio player is on.

Many people advice me not to regap plugs, I should be getting those that has already pre-gap from factory. Anyone can help meon this cause i want to refit my HKS Iridiums S35i again.

[tRUkbOY]

I have this exact same problem on my S1 Stagea where it also does a little backfire/miss on gear changes if I'm treading it. The other thing is it sometimes (usually after starting after it has already been warmed up) it runs likes its flooded. After about half a block of not wanting to rev up it eventually clears its self & off we go.

I have cleaned the coils (no obvious cracks that I could see but will check them again), regapped plugs down to 0.8 & have just cleaned out A/F meter. If that doesn't do it then I'll try cleaning out the AAC valve.

Has anyone else had probs with the "flooding"?

[driftmeister]

My problem came back and idling suffer quite badly. So i upgraded the battery to a higher capacity. But still the same also.

Looks like i have to get the Splitfire Coil Pack. Will try to regap the plug first and see how it goes.

[Booya]

So same propblem hey with upgrading the battery.

My mate came around this morning and helped me out.

Changed over the spark plugs to 0.8 gap but still same problems.

He said it either the injectors or coil packs. So he checked by removing the power supply to each injector and found that coil 3 was not firing.

So i need to either replace this one. WHat do you think?

Or get a complete set of splitfires?

[driftmeister]

This time finally solved. After 3-4 hours checking, changing back to my HKS plug, adjsted timing (mine was almost max retard), then the idling became better / more stable but still misfire during 4-5k rpm. disconnected my car alarm cause there are wires join to the RPM for the immobiliser. Remove all coil pack then exchange one by one. Finally found it to be Coil Pack problem and guess what...its coil 3 too. My mechanic seem to have a spare so now all is smooth & rev happy to redline.

I hear that 34GTR coil pack are the same. is that true cause the part no for splitfire are diferent for GTT & GTR. Anyone know whether GTR ori coil pack is also the same?

Jaffri

[ross80]

I have just pulled out my ignition coils and ran silicon around the top and bottom of coil. Basically covered the whole thing.

Is the next step after they have dried wrapping the whole coil in electrical tape and then cleaning plugs on coils with electronic contact cleaner?

I have just bought some new plugs and hopefully that will solve the problem.

The silicon gasket glue material is resistant to temperatures of 350 degrees is that enough?

Cheers

Ross

[Booya]

Ended up ordering some splitfires so hopefully they will be here soon.

Will need to reset the ECU once i get them as the car is constantly misfiring. Where is the ECU in the 34?

Ive heard disconnecting the battery and holding the break resets it, but ive also that you should disconect the ECU

[driftmeister]

Been almost a week & a half, all smooth & power still there. No misfiring at all. Pls check you timing, may help a bit since retard basically give a low sparks so the injectors lean out the spark plugs. Mine is current arount 15 to 20 degree advance. Engine felt light and effortless to drive now.

Splitfires would be great but the managed to get 2nd hand replacement for 1 pc only around $50 . Well worth it considerng i've been suffering this for almost 5 months!!.

Booya hope you get ur replacement soon but if you have a friend who you can loan 1 coil pack to just check which is faulty then u know u can keep the good ones for future or probably sell to some mates of yours.

[Booya]

Theyve just sent my order off today so i hope i get them before the long easter weekend. Cant wiat to go for a drive without it spluttering along.

Its definately the coil though, ive tested this out and i know exactly which one it is! bloddy coils. Looked for a second hand one but only one i could get was 80 buks for one from this site so i opted for new and sell the old ones.

Cost 580- maybe $50*5 for each working coil = 330 total

Not bad i say anyway

[driftmeister]

I too wanted to get Splitfires but if i order from my local supplier it will cost me RM$ 3500 (malaysia currency) per set, equavalent to around $1000 AUS dollar. Not worth it.

Sell at $60-80 eah also will make ur mates happy, the smile on their face after fixing the problem is PRICELESS!

Check ur timing yet? idling will be better if set correctly, just the 4-5k rpm will misfire. Better than jerky traffic lights idling.

[khunjeng]

I too wanted to get Splitfires but if i order from my local supplier it will cost me RM$ 3500 (malaysia currency) per set, equavalent to around $1000 AUS dollar. Not worth it.

Sell at $60-80 eah also will make ur mates happy, the smile on their face after fixing the problem is PRICELESS!

Check ur timing yet? idling will be better if set correctly, just the 4-5k rpm will misfire. Better than jerky traffic lights idling.

hi guys

been reading with intrest as I have these issues. will replace the plugs and at the same time have a look at the coil packs to see whats going on.

One question, cos I'm a noob, how do you check the timing??

[driftmeister]

My mechanic had something like the handheld Nissan Consult, but different type that can check other car makes too. Another way is to use the timing light but i have never tried that before myself. I heard NEO engines need to unplug a socket for throttle sensor (i think) before doing the timing but my mech just advance without unplug anything. The reading was showing 11 deg on the Consult which is way too low & advance to around 15 deg +.

Felt great after that....

[GTsauRus]

Guide to fixing missfiring issues.

Step 1: Gap spark plugs to 0.8mm if you're running over standard boost. (Copper plugs seem to work fine and are cheap). If this does not work try Step 2.

Step 2: Insulate the coils with good quality electrical tape, or for a more permanent approach, araldite them. If this does not work, try Step 3.

Step 3: Buy some splitfires.

I don't think 2 cars are really the same. Mine had major missfiring issues and major discolouration due to arcing on ALL the coils. Mine was solved with just Step 1. Does not missfire at all on boost anymore. If/when it does start missfiring again I'll change the plugs and look into the araldite trick before spending over $500 on splitfires.

Fixxxer

I have run my gtr at 0.8 bar since september decided to give higher boost a run 1.2 bar and got bad missing then replaced denso irridiums @ 0.9mm with ngk irridiums pre gapped to 1.1mm and it started missing at 0.8 bar Hmmmm.

Found this topic decided to clean all the coils and stretch the carbon contact springs and put permatex ultra blue silicon around the bottom of the coils, it looked to me like the coils had been tracking from where the rubber boot slips on due to a build up of engine bay grime.

So now it runs clean at 1.2 bar

Got low boost set back at 0.8 for daily driving

Thanks all for the info

[JD-33]

seems like this is common for skylines..

glad this topic got started cause after turning my boost up to 0.75 bar ive been having the same problem! ..

initially bought a TurboTech boost controller (in in the $22 controller thread) , and upped the boost from 0.6 bar to 0.75, ever since i did that ive been hitting that flat spot .. but i only hit it in 4th and 5th gear ,, (1st 2nd and 3rd are strong as) ..

gonna turn the boost back down to 0.6 tomorrow (until I fix my coils) ..

This turnin of the boost back to 0.6 should return it to normal?

or since having the boost at .75 could have caused permanent damage?

Cheers

-JD

[Booya]

Hey all,

Well finally got my splitfires now after waiting 3 weeks from Nengun.

Cost $587

Fitted them in last night and now my baby is running like a dream.

I was getting my car missfire all the time, due to one coil being bad.

I also noticed that the TCS & engine lights were coming on because of this and since replacing the coils they have now gone.

I also resetted the ECU since running the car everynow and then for 3 weeks would be giving the ecu some bad readings.

I noticed that it reset the ECU (after disconnecting the neg terminal) that you see the dash, clock, and middle display lights do a check to make sure all is working, you will also notice that the clock resets its time.

Steps i took to fix my problem.

1. regap sparks

2. check coil packs (all were ok)

3. replace coils (worked for me)

[driftmeister]

It's been a month half since i fixed my misfiring problem and car still drives like a dream with no hiccup. One thing my friends notice while following behind is that my exhaust spits fire while upshift and sometime when i downshift (heel & toe). Looks great and sure scare quite a number of people to stay way behind! hehehe

Now i want to install Electronic Bosst controller, wonder upping the boost may bring back the misfiring problems espescially in 3rd or 4th? Since i am currently enjoying the pedal to the metal feeling right now.

What is a safe boost for R34GTT before the misfiring happens? I was told to install FCD (Fuel Cut Defencer). Would this help to avoid any misfiring? Appreciate everyone's advice.

[Limmy]

Hi. I'm a newbie that just bought a r32 gts-t. Running stock boost

I think i have this problem with missfiring. But im not too sure.

It happens when im in 1st gear and i put my foot down, the car would be pulling. And after certain revs . it feels like the car doesnt want to pull anymore. and just makes a hissing noise from the turbo. it feels like theres a limit of boost. This is when i would change gear. and sometimes depending how much accell i put. it mite do it again. or be smooth.

I've noticed it happens sometimes when im too anxious on the pedal and changin gears fast.

Usually happen near high revs.

Could this be the same problem?

[Craig Baxter]

hey guys, my friend had this problem with his 1jz soarer for ages and found to be same problem, cracks in the coils, he went through 2 sets of iridium plugs and was pulling his hair out for a month then he took the coils out and tested them they were fine but found hairline fractures in them, he is a mechanic and has seen problems like this on early ford distributers crossfiring and he found that covering the crack in araldite stops the arking between them as it does not conduct electricity.

he coated the coils with a layer of araldite over all the cracks and found he was able to hit full boost with no problems and has not had a problem for almost a yr now, he pulled them out last week to check them and were fine, also stopped the crack widening aswell. i think someone should give it a try as it is a dodgy way to do it but it is a slightly better method than tape (coming loose etc)

but remember let the araldite set!! usually about 6 hrs is fine but i think you can also get the 5 min araldite for quick adhesive.. well hope it helps someone anyway.

[cry41t]

I recently upgraded my boost controller from a t-piece to an eboost (digital), as soon as the install was complete misfiring was occurring as well as a flat spot between certain rev limits.

My mechanic tried everything from plugs, timing, settings etc, then i was advised from another mechanic that it was my coil packs (after testing) and the flat spot occured due to all my upgrades (front mount, forgies, ebc, exhaust etc etc) and the standard fuel pump was not working sufficiently for the power output.

I immediately changed my standard coil packs to splitfire coil packs which solved the misfiring.

And just recently had a walbro fuel pump installed which has solved the flat spot.

The car is now going smoother than ever and has actually increased its power significantly.

Im not saying this will provide the same solutions for everyone, but it may help someone.

Edited July 9, 2006 by cry41t