ive searched for hours and cant find much, so here goes.

its a 92 j spec tt, has boost jets and chip, runs well under normal driving or if i build the revs up to 3-4k and then floor it, but if i floor it from under 3k its holding back alot! both boost gauges stay constant (0.9 bar) plus ive done a leak test, all filters and plugs changed, cleaned elec conectors afew times, decated it and by passed the carbon canister, i cant think of anythin else to try to stop it holding back under full throttle, but even when i let the revs build it still doesnt go as well as it should. any sugestions???

ive searched for hours and cant find much, so here goes.

its a 92 j spec tt, has boost jets and chip, runs well under normal driving or if i build the revs up to 3-4k and then floor it, but if i floor it from under 3k its holding back alot! both boost gauges stay constant (0.9 bar) plus ive done a leak test, all filters and plugs changed, cleaned elec conectors afew times, decated it and by passed the carbon canister, i cant think of anythin else to try to stop it holding back under full throttle, but even when i let the revs build it still doesnt go as well as it should. any sugestions???

Could be a Faulty Air flow meter?

Yeah sounds just like mine was with burnt out maf

 

Most would say boost leak but i read you already checked it.

 

At least a maf is an easy swap test!

Happened on my skyline turned out to be afm, BUT Same thing happened on me 300 zx 92 j spec boost jets etc And it was a faulty coil. If your in my area come over as i have spare we could try. Muffin.

cheers for the reply chaps

ive just re cleaned the conections to the maf, should it only have 4 pins on it? yet the cable has 5?? and is there another way to test if its faulty other then swopping for a known good one??

Have you tried diag test yet bud?

yeah, it bought up 02 sensors, but that was a short in the wiring, which i sorted. it was an auto when i got it, but the box was kaput, so i did a manual conversion on it, dont know if thats got anythin to do with it, but zedworld did a conzult on it a shortly after which bought up nowt.

Is it like a missfire

The ECU could be sensing detonation and knocking the timing back. Det sensing is reduced substantially over 3000 RPM (or there abouts). I have the same issue now I have a more aggressive chip in it.

can you here any det?

I can't :) There's no interior in my car and it drones like crazy. Doesn't weigh much though and goes like stink. Fun on the car club hill climbs :)

theres no detination, but if there was it wud reduce my boost wouldnt it?? and its definatly not miss firing. 1 thing i noticed wen i was under it, the 2 exhaust down pipes didnt have the 2 smaller pipes that go to the egr valve on them, is this normal for a series 2?

doh! not you lol

ah???

bugger lol

wot r u goin on about?

craziness

id have gone for dimented, unless he's the guy that sold me this pile of sh?t, then id go for absolute f?kin w?nker!!

Dimenteds about right sorry guys not with it today.

Anyway... id try and get hold of afm to try first.

is the one thats on it rite with only 4 pins, but a 5 pin connector from the loom?

yeah, it bought up 02 sensors, but that was a short in the wiring, which i sorted. it was an auto when i got it, but the box was kaput, so i did a manual conversion on it, dont know if thats got anythin to do with it, but zedworld did a conzult on it a shortly after which bought up nowt.

 

 

O2 sensors won't make that much difference at high revs, closed loop system etc.

The ECU could be sensing detonation and knocking the timing back. Det sensing is reduced substantially over 3000 RPM (or there abouts). I have the same issue now I have a more aggressive chip in it.

 

Nope, not at high revs, once again closed loop system, it just blows hell out the engine if you don't hear the det yourself.

umm.. not sure. anyone?

theres no detination, but if there was it wud reduce my boost wouldnt it?? and its definatly not miss firing. 1 thing i noticed wen i was under it, the 2 exhaust down pipes didnt have the 2 smaller pipes that go to the egr valve on them, is this normal for a series 2?

 

 

Yes, almost certainly no EGR on a Series II car.

 

Concentrate on the airflow sensor for now.

but, it had an engine swop at some point for a series 1, and it still has the egr attached the it. i disconected the hoses from it and made them air tight, but could this have somethin to do with it? again this replacement was done by zedworld