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Weird Noise, Lack Of Performance.. Doesnt Seem Like Missfire

GTAAAH

By GTAAAH,
in Engines & Forced Induction

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GTAAAH Mentor

GTAAAH

Posted
Posted (edited)

Mm, so i have this weird missfire-like problem in my GTR

The sound isn't really coming from the engine (my old gts-t used to missfire and you could hear it at the engine, totally different sound and it would dramatically affect engine behaviour, not just slow the revving down a bit) it sounds more like it's coming through the turbo, like a surging sucking sound, except more like a sprinkler like it's sucking and cutting off reallly fast.

It only happens at high revs in 2nd or 3rd gear, and i have changed gap on the gtr a few times, and tried 1 and .8 regaps and it still happens.

But yeh, it doesn't seem like a missfire (compared to other missfires, where they've made the engine all jittery and sounded like revs cutting), and changing gaps and plugs, and checking coils for cracks made no difference

So yeh, any suggestions?

atm im just thinking i should go get some splitfires and throw em in coz they gonna need to be replaced eventually anyway

Edited by GTAAAH
R34GTFOUR Mentor

R34GTFOUR

Posted
Posted

are you talking about the gtr or the gtst? either way doesnt make any difference just interested cause you started on the gtr and finished on the gtst lol.

Regapping to .8 is still quite big, i would maybe drop it down a bit more. A mates 200sx had his gapped at .7 and it had a "fluffy" missfire across the rev range, like it was blowing the spark out, dropped the gap down to .5 and its been sweet and he doesnt have any problems at idle at the gap either.

What computer you running? im guessing you have minimum of safc to run the z32

GTAAAH Mentor

GTAAAH

Posted
  • Author
Posted (edited)

OH yeh asking about the GTR, i kept confusing myself but yeh, got the same probs on both of them so was assuming it had to be the same thing causing it coz it sounded and seemed exactly the same

:edited out the gtst bit, was confusing as hell lol:

the gtr is totally standard, standard boost etc

Also the gapping is just a fix for screwed packs anyway isn't it really?

Edited by GTAAAH

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