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

[Nails]

hey guys i just got my new exhaust system on today, and my car has been missing since! why would it do it after i get the exhaust on? i have a 3inch split stainless dump, gutted cat, to 3inch stainless kakimoto exhaust. any ideas, i have just had my 100k service, it only misses when it hits 2nd stage boost at 7psi, after 4 1/2 rpm ?? ideas would be awsome

My R33 has a similar exhaust setup and was misfiring similar to yours, I tried taking the coils out, having a look at them and cleaning them up with wd40 however that was obviously not enough, as after a week of OK operation it started running like crap again. I just put Spitfire coils in today, ordered from perfectrun for bout 465 all up, and it is running very smooth now.

[jutstar]

well i am stoked! wrapped the bastard up and she runs perfect! its amazing how such a TINY hairline crack can cause it to run so bad!

thanks nightman, if not for this thread i wouldnt have my car running so soon!

Had my gtst R33 S2 (stock) for 2 years and first got this problem tonight dragin a VT v8 commodore home ffrom work, we both put our foots down and I just got stuttering from the engine at 4000rpm, hope its the same problem as the rest of u, so its an easy fix.

[Nothing(V)an]

i had the same problem a while back and a set of iridium plugs fixed the problem perfectly, just got a front mount and exhaust installed and its back, possibly even worse than b4. Does anyone think it could be the fuel filter or fuel pump?

[jutstar]

Just taped up the coil packs, but didn't fix the problem, will change spark plugs next, probably been about 30,000km's since they were changed.

[clkngezz]

JUTSTAR: dont forget to gapp them at .8mm, i get splitfires this week hopefully by wednesday, dont u worry ill be posting if it fixes the problem

[Nothing(V)an]

JUTSTAR: dont forget to gapp them at .8mm, i get splitfires this week hopefully by wednesday, dont u worry ill be posting if it fixes the problem

covered my coils in selleys industrial strength silicon, left them overnight and problem solvered, havent had a single missfire since. Got a whole new problem now.

[clkngezz]

lol what is the problem now is it still got to do with missing? but well done, i am fitting my coilpacks tonight split fires baby yeah

[Nothing(V)an]

the boosting feels really flat now, it sounds like its boosting and the guage(stock one) shows that the boost is increasing at 4.5rpm but the car doesnt seem to be picking up quick enough. Also at night when it gets cold, the boost almost gets up to the +7 on the stock guage which cant be good. i got fmic, turbo-back exhaust, stock ecu, no boost controller. Im going to take it in 4 a tune soon, hopefully they can sort it out.

[voodoogtr]

hi to everyone!

I've expiriencing the same problem on my R32 GT-R, engine missfire after 4000rpm ander full load(boost 0.8 bar) and engine cut off after some time if I keep running . But I can't solve this problem. I've already tryed to replace ign coil from 3 cars and they was runnig smoofly. I found that where was problem with wiring jaker of the ign coils, I removed jakers in conect wiring directly and sealed with silicone, 

esterday i sealed ign coils 

like you did, and engine start working well but only if I run on under 1/2 throthle. In other words main problem still remained.

before any work on this problem i found that #3,#4,#6 cyl were not working properly. and even after exchanging coils 3 times they not worked. after fixing connection jaker of ign coils -- #3 and #6 working OK, but #4 NOT 

spark plugs - set of new greddy 8 plugs (gap 1.1)

power transistor - was replaced

new fuel pump

injector were cheked and they are OK

and now i want to ask you

what else can cause missfiring on RB26DETT?

Well, looks like i've described my problem and now I'm waiting of your advises on how to make my godzilla run like mad!

and please excuse me for any mistakes in english it's not my native language

I'm from Russia

Far East. Sakhalin Island (near to Japan)

Edited August 10, 2007 by voodoogtr

[BlueStagea]

Confusing!

All this tells me, is that no-one actually knows how to "fix" the problem. Some have been successful, but others have found how to just mask the problem.

My mechanic is absolutely stumped. I am pissing him off taking my car in every few days when the 'Check Engine' light comes on, and I'm getting impatient.

The car is under a mechanical warranty, which covers faulty parts, but the mechanic cant find what is faulty. So far, two coils have been replaced, and all the others have been extensively tested (but not in the car - how does that work?) and the plugs have been replaced.

I get the Check Engine light come on intermittently, and sometimes the car will idle roughly, like its dropped a cylinder.

WTF is going on with these cars? I thought Nissans were reliable!

Where do I go next?

A 'For Sale' sign!?

Edited August 12, 2007 by BlueStagea

[Nothing(V)an]

The car is under a mechanical warranty, which covers faulty parts, but the mechanic cant find what is faulty. So far, two coils have been replaced, and all the others have been extensively tested (but not in the car - how does that work?) and the plugs have been replaced.

They check the coils using a megameter (or similar name), checks the resistance of the coil which tells em if its fu@#ed.

[BlueStagea]

They check the coils using a megameter (or similar name), checks the resistance of the coil which tells em if its fu@#ed.

Thanks.

My mechanic had checked them and was confident enough to need two replaced, but the warranty co. wanted them checked by their company, so they were shipped off without the car.

I kind of expected that they wouldnt find any fault with the rest of them, and they didnt. Not sure if its because they are working for the warranty company or if they are too hard to test out of the car.

I'm kind of losing faith with the whole process.

Where to from now?

[Rolls]

Where to from now?

Replace all the coils with splitfires and get new plugs @ 0.8mm

Next step is to make sure the car isn't running overly rich and this means you need an even better spark to properly ignite the mixture. Ie get it remaped (or aftermarket management) and make sure your sensors are all functioning correctly. If you can't afford this put the stock exhaust back on so run stock boost, this will stop it running it so rich also.

A combination of all 3 of these will fix your misfire providing it is spark related.

WTF is going on with these cars? I thought Nissans were reliable!

They were when they came out of the factory 20 years ago, now they are getting old and parts start failing.

Edited August 12, 2007 by Rolls

[BlueStagea]

Replace all the coils with splitfires and get new plugs @ 0.8mm

Next step is to make sure the car isn't running overly rich and this means you need an even better spark to properly ignite the mixture. Ie get it remaped (or aftermarket management) and make sure your sensors are all functioning correctly. If you can't afford this put the stock exhaust back on so run stock boost, this will stop it running it so rich also.

A combination of all 3 of these will fix your misfire providing it is spark related.

They were when they came out of the factory 20 years ago, now they are getting old and parts start failing.

The car is only 7 years old and only at 75000 k's. Plugs are new, exhaust is standard, car is non-turbo so boost wont be an issue. Running on 98 (BP Ultimate). Warranty wont replace parts unlesss found faulty! I'm sure my mechanic will love me telling them what to do, but you guys have experienced this before, so I'm open to ideas.

Cheers

Edited August 12, 2007 by BlueStagea

[voodoogtr]

I've already tried install the set of NEW SPLITFIRE'S but it's not helped

At last I'm thinkig of problem in main wiring of engine. Today will try to find out any cuted wires from ECU to engine. My friend got problem like mine and he found some wires were cuted in main wiring!!! Looks like Nissan makes their cars from some junk or shit!

I don't know exactly but it seem to be like this!

[BlueStagea]

I've already tried install the set of NEW SPLITFIRE'S but it's not helped

Looks like Nissan makes their cars from some junk or shit!

Your english is great! Its right to the point. I am starting to think the same way!

Very frustrating.

I am holding off getting Splitfires.

Edited August 13, 2007 by BlueStagea

[Noel]

I've already tried install the set of NEW SPLITFIRE'S but it's not helped

same problem...threw in a set of splitfires sat & prob went away over weekend but now its back but only sometimes & notice worse when cold...i have ngk iridium's heat range 6 gapped at 0.8mm splitfires & running 8.5psi with r34 SMIC & pod...everything else is std...what could it be? afm? o2 sensor? i was thinking maybe try going back to heat range 5 plugs as before i swapped to the iridiums it was fine?

any thoughts?

[voodoogtr]

I've already tested my O2 sensors and AFM's and they work perfectly! I've tried different gap on my Apexi 8 plugs(0.8 and 1.0), it's not matter for me at all!

If anybody with same problem could test main wiring to find out any crack there it will be great!

As for me I dont know any special trained mechanic to do this for me fo cheap so I'll remove main wiring and check it by myself for free. And of couse I'll inform you 'bout my progress .

[voodoogtr]

Well ... the weather outside is weird so I've desided not work with my car but find out any solutions to described problem.

1. I found that Crank Angle Sensor replacement helped to solve problem. will replace with one from working engine.

2. Also I suppose it might be problem with Intake Air Temp sensor failure, because after short run engine heats up and problems occours from 1500rpm, but on such low rmps it much harder to hear.

3. I also planing to check every relay , maybe something wrong there.

4. And at last main engine wiring harness...check for any cracks

As I suppose my problem not actually missfiring but "rich & retard" causing missfire.

Or possible too lean ..... but I don't know how to find out am i runing rich or lean.

Any thoughts or suggestions ?

[voodoogtr]

Well I've found what was wrong with my car!!!!

It was TPS , but it was working only for percentage of opening throttle and not working idle switch. This caused ecu to inproper fuel and timing operation!!!! And there were no eror codes on ecu.

And seems to me I also in need of new splitfires. Because engine work not so smooth on high load of boost.

Good luck you friends to find out yours solutions.

Edited August 16, 2007 by voodoogtr