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

[joshw33]

by the if anyone needs coil packs i bought splitfires for $570 from kudos motorsport

http://www.kudosmotorsports.com/catalog/r33-gts25t-electrical-fuel-system-c-21_22_26_132.html

[Rolls]

i had the same problem as soon as i hit 4000-5000 rpm it it will missfire even on low boost

i put new plugs in it [bPCR6E 0.8mm] ran ok on low boost but as soon as you put boost in to it it runs like shit

so i tried to silicon the coil pack still no good then i went and bought new coil packs splitfires runs heaps better

no missfire as soon as it comes on boost it starts pulling and then about 4000-5000 rpm it doesn't seems to pull as hard

and then it starts pulling again so im thinking i might need to try a colder plug or smaller gap

any suggestions would be appreciated thanks

Sounds like it is just running the standard tune, you get a torque dip around 4-5000 rpm (normally peak torque) due to the tune richening up for safety, pretty normal and if you look at dyno sheets of stock tunes you'll see this common dip in the midrange.

Remap should sort you out.

[TJHill]

I have just bought a R32 and it does the same thing. When I first drove it home it would start misfiring at 3000 rpm but after mounting the ignitor so it wasn't floating on top of motor and fixing dodgy wiring it now gets to 4000-4500 rpm before misfiring. Also when I tried to give it a squirt it reached 4000 rpm in 3rd and just wouldn't rev any harder. Didn't misfire or anything, just wouldn't rev any harder.

I have been told to check spark plugs, coil packs, and the wrap tape round the spark plug technique. Aswell as being told it could be crank angle sensor, oxygen sensor, blown head gasket, or even pistons and rings.

I have just grabbed some standard plugs and I am going to check coil packs as I can't afford those yet and have it booked in for compression test.

Anymore advice I can be given would be highly appreciated!

[sam_c]

Hi guys,

I am having a misfire problem with my series 1 r33 however it is occuring at all rpm ranges, anything more than 25% throttle and even at idle. I hadn't driven it in 7 weeks because i broke my ankle and when i started driving it again it was running absolutely fine for 3 days until last night when i was taking off lightly from a set of lights.

I am running fmic, emanage ultimate ecu, avc-r boost controller, 3 inch exhaust, pod filter, bosch 040 fuel pump, stock turbo at 10psi. The spark plugs were replaced 4 months ago, so I am thinking it is possibly coilpacks. Has anyone experienced a similar issue? I don't think it is fuel or ecu related as I have been running the pump and ecu in my car for 6 months with no problems.

Any help would be much appreciated.

- Sam

[Dan_J]

now i may have a similar problem:

on the rb20det running 10psi and plugs at 1.1 i've changed my regular coil packs to a spare set i had laying around that i believe are newer/ in better condition.

now the problem i'm getting on full throttle is a splutter from 4k to 6k RPM, i already get a back fire (exhaust POP) on/off throttle at around 3k. my original coils dont splutter above 4k so is the splutter the missfire we are talking about or just wear and tear ?

[Rolls]

seriously guys read the thread there is 20 pages of answers

[Dan_J]

^thats the problem

[Galois]

How do you know the spare set wasn't in just as bad a condition?

[Paradizzle]

Probably already posted but.. I thought I had a misfire but it was in fact the ball bearing in the manual boost controller that had rusted which was causing big stutters under acceleration. Something worth checking out, I didn't drive my car for approx 3 weeks and then it started happening.

[mikeyR33-T]

Hey fellas i have an SAFC and i think i may have the same problem!!

And ive just had it tuned also (by a very respected tuner)

Thing is he tuned my car on a 27degree day and it gets worse when the weather gets colder!

Maybe its not a miss??

I also get a pop out of my zorst in between gear changes is that related??

Cheers

Hi hoping you can help or anyone? i am new to skylines, just wondering if this is right (ill try explain in my own words!) driving the skyline, increasing throttle, rpm hits and then about a half second delay then the goosh boost sound comes on, then further up the rpm again around 7000 rpm another 1 sec delay like the car hits 7000 and holds it for a second then the boost kicks in? is this normal for the car to hold for a second before the boost hits in? doesnt feel right to accelerate and then feel it spool up but takes a second for that boost pop sound? can someone enlighten ME

[Rolls]

What is a 'delay' ? Is it a misfire (pop pop pop)? Does the engine completely cut ignition? Does the engine splutter, does the engine just make no power? Is the engine pinging/detonating (sounds like a can of nails being rattled around) ?

Answer these questions and we can help you.

increasing throttle, rpm hits and then about a half second delay then the goosh boost sound comes on, then further up the rpm again around 7000 rpm another 1 sec delay like the car hits 7000 and holds it for a second then the boost kicks in?

This makes absolutely no sense. "Rpm hits" what doest his mean, rpm hits what? at 7000rpm theres a 1 second delay before it hits 7000rpm again?? Sense makes none.

What does "boost kicks in" mean?

Edited September 9, 2011 by Rolls

[mikeyR33-T]

What is a 'delay' ? Is it a misfire (pop pop pop)? Does the engine completely cut ignition? Does the engine splutter, does the engine just make no power? Is the engine pinging/detonating (sounds like a can of nails being rattled around) ?

Answer these questions and we can help you.

This makes absolutely no sense. "Rpm hits" what doest his mean, rpm hits what? at 7000rpm theres a 1 second delay before it hits 7000rpm again?? Sense makes none.

What does "boost kicks in" mean?

im new sorry, and its like there a half sec of nothing then a pop kinda sound when the turbo cuts in? and not ignitition its like it holds for a second before it pop or makes the turbo sound like a pop as there is no BOV there is a slight sound at the rear? and not rattling just puff or pop sound when it gets to a certain RPM range and then it feels as if the turbo cuts in but its like a lag before the turbo cuts in and or pops

[Galois]

I'm a little confused by the description mate, and think that it would greatly help you to read a fair bit of this thread (at least the last 5-10 pages), then see if the problems you describe are similar to those others have had fixed.

[carcass]

I checked the tape i put on my coils after having it on for a good few months and the tape was still exacly how i left it.

so it depends on how you wrap the coils and what quality tape you use.

Go to an electrical wholesaler and ask for "self amalgamating tape" it stretches back on to itself. The best insulator and is resistant to high temps too. Good shit for exactly this type of application. Better late than never

Edited October 8, 2011 by carcass

[pipster11]

i got my tape from my local chandlery

They didn't know what self amalgamating tape was, theirs is called RUBBAWELD

probably cheaper from an electrical wholesaler (mine was $12.95)

put it on, (bought 2 rolls but only used 1), seems pretty good

i don't think my coils were dead yet but they'll last a little longer now

[DVSTRK]

I have a miss in my r32 gtr after about 4500rpm, car still pulls but its asif its spluttering whilst boost is on. Im running splitfire coilpacks with std ngk plugs gapped to .6, boost is set to 16psi with a tuned pfc ecu and basic bolt ons intake/exhaust/fuel pump/injectors. Spark plugs have been in for about 4-5000kms, took them out and they look fine, also realised the car is running a bit rich, alot of poping going on wen on light throttle between gear changes.

Any ideas?

Edited October 31, 2011 by DVSTRK

[Galois]

Could the plugs be too cold?

Wrong plugs can lead to a world of frustration

Edited November 1, 2011 by Galois

[DVSTRK]

Could the plugs be too cold?

Wrong plugs can lead to a world of frustration

Not sure, i had the impression that as long as the spark plugs are changed regularly it doesnt make much difference with expensive ones, i realised it happend after one of those really hot days last week or so, cars running temp was stable, is it possible for the sparkiz to just let go or fail at certain revs, recently after one of the miss/splutter expirience the car dropped a cylinder sounded like a rexy, check that all coilpack plug ins were in proper contact, no issues there but after i turned the car back on all 6 cylinders were firing.

Edited November 1, 2011 by DVSTRK

[Galois]

^Hate to say it, but that was what my r34 did when it's stock coilpacks went. How old are the splitfires?

[DVSTRK]

^Hate to say it, but that was what my r34 did when it's stock coilpacks went. How old are the splitfires?

No more than a year old, i also noticed the splutter happens after i drive the car for abit.

Grabbed some iriway plugs, going to chuck em in soon, hopefuly its just a faulty plug.