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Hi guys, have been having an issue with hesitation or missing.

At first it only happened when the car came on boost hard, it would hesitate badly, not smooth boost delivery, choppy. But this does not happen all the time, sometimes it is fine when it is on boost.

Lately it feels like it is hesitating/missing more just when driving around normally, ie: off boost under a bit of throttle. Again, this does not occur all the time either. Sometimes on idle it feels rough and sounds like its missing, other times it idles fine.

Yesterday, when I started it up it sounded like a WRX for a few minutes, then it went back to sounding normal.

Cant be air flow metres as I run a Vipec which doesnt need them. I have the usual bolt on upgrades; -5s, bigger injectors, fuel rail, fuel pump, cam gears, zorst, etc.

Car had been running like a dream since tune, this problem has just started up in last couple of weeks or so.

Coilpacks are still the stockies, do you rekon this is my problem? Are coilpack issues limited to off boost or on boost or can it be both as per what is happening with my car??

Or what else do you think could be causing my issues?

Thanks people

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most likely wiring or coilpacks. sounds more like coils though. common problem. next time it starts to misfire pull off the leads one at a time and when you pull a lead off and the noise doesn't change you know it's that cylinder. then replace the coil.

have you tried cleaning all the jackets?

you could always upgrade to spitfires but it's not always needed.

how many k's has it done?

does it run fine when you first start driving, but after a little while gets worse. if so i'd say the coils. there is a ghetto mod that some have used to fix it up, but i went the spitfires and it was worth every dollar after being able to floor it through the rev range!

I'd try find someone you can borrow a set off for a few days. Surely someone there in NSW can let you have a borrow of a set for a day or two (and you put yours in thiers)... if yours runs great and thiers suddenly crap then you know for sure

Better than spending $600+ on something that might not even fix the problem.

That said, R34 ignition setup isnt the best, so its fairly likely but still IMO diagnose before spending :D

Also go over all the connections with contact cleaner, you never know, could just be an average connection.

Also what plugs/gap? How long since a service?

Service was only done ~1200 Klms ago. Not sure on the brand of the plugs or the gap but new ones went in when it got tuned ~ a month ago.

Maybe I should put new coils in anyway considering Ive replaced most of the other bolt on stuff with new items??

yeah try plugs and gaps.

Also could be a leak in your plumbing if u aren't running stock BOV's

If it had a leak, should it play up all the time? Sometimes there doesnt seem to be a problem then it comes back.

Maybe 1 of the coils or plugs is working on a part time casual basis.

in my old 180 had the slightest of slightest leak in my plumbing and it would hesitate sometimes and i would get less boost. I tightened all my clamps and tightened BOV. all good afterwards.

You've got a hard pipe kit dont u?

in my old 180 had the slightest of slightest leak in my plumbing and it would hesitate sometimes and i would get less boost. I tightened all my clamps and tightened BOV. all good afterwards.

You've got a hard pipe kit dont u?

Wouldn't start running like crap and sounding like a WRX when you turn it on at cold start though and then suddenly pick up to perfect. to intermittent for it to be a leak imo. if you have plenty $$ to spend get some new coils and i'm almost certain the problem will be gone.

this may be a silly question,

but have you been switching fuels?? maybe the tune was carried out on a different mix of fuel...

I only use bp ultimate with no probs, vpower on the otherhand was like chopping of the cars' balls!

(last time i used it i noticed the missfiring/hesitation/rought starts...)

Yeah I do switch between fuels but my tuner told me that it would be OK to do so.

Will most likely get new Coilpacks, reading other threads it sounds like the problem came and went for others also until they replaced those.

This morning the car ran pretty good. No hesitation while driving and boosting to 1.2 Bar with no problem. On idle it sounded like it had a few lumps in it but it wasnt a rough shaky idle.

remove coilpack, delicatly place it on a bench and then smash it with a hammer, put coilpack back in.. if problem persists.. get new coilpack, repeat process for each coilpack or until all 6 are royal blue in colour. works everytime. :)

cheers

linton

remove coilpack, delicatly place it on a bench and then smash it with a hammer, put coilpack back in.. if problem persists.. get new coilpack, repeat process for each coilpack or until all 6 are royal blue in colour. works everytime. :banana:

cheers

linton

Nice one hehe!

have you looked at the coils yet man? a friend with a 180 cracked a stock coilpack after raising the boost quite a bit higher; he pulled them out and found a crack in one of the coils so he used some silicone to seal it and it was fine after that.....ps: he put in new ones a week or 2 later.

goodluck man

you did have problems with your injectors before ? were they all replaced?

maybe it is another injector issue. I would get someone to check it out before spending lots of money on parts when you are not sure what the issue actually is.

All the injectors got replaced with brand new items.

I think this problem used to happen from time to time when I first bought the car when it was stock so a coil may have been slowly on the way out back then.

Its an R34 GTR yes, but it is still 10 years old. There are others on this forum with R34 GTRs that have had very similar problems.

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