Urgent Help Needed

[ECR 033]

Car:

89 R32 GTR

Problem:

Misfire at idle and when i try to hold it at a certain amount of revs (e.g) 1500, 2000, 2700, etc etc., it idles at 1100-1200 rpm, and if i rev it to about 3000rpm and let my foot of it tries to stall on me. (1 out of every 3 times)

it revs up fine and boosts ok. but wont sit at any certain amount of revs.

tried:

coilpacks

plugs

cleaned/checked AFM

Replace coilpack wiring harness.

replaced all intercooler clamps etc.

any help would be great.

[R31Nismoid]

full list of mods please

[ECR 033]

full list of mods please

High mount to4z, 50mm turbosmart ext. gate.

stock afm's , and stock 02 sensors

fresh engine. (500km's old)

stock computer (stock with stream tokyo power base tune)

10psi boost

stock plumb back bov's

[R31Nismoid]

where are the AFM's... likely too close to the comp housing.

Why you running all that stock gear with a T04Z anyhow? (and dont say 'running in' the motor)

[ECR 033]

where are the AFM's... likely too close to the comp housing.

Why you running all that stock gear with a T04Z anyhow? (and dont say 'running in' the motor)

i have 700cc injectors to go in, and plan to get a power fc, but i wont spend the coin on a power fc incase i need the cash to fix whats casuing the misfire.

so just want to get that sorted first.

don't think the afm's are too close if they were any further from the turbo they would be outside of the car. i can barely fit a thin hks filter between the afm's and the washer bottle and passenger headlight.

i just went and checked for error codes again and got: #21 (ignition signal system) my manual says: ignition signal is not generated continuously even though crank angle sensor is entered (dissconection between power transistor and control unit).

i check voltages to the coil packs and igniter but how do i check the sginal wire?

[MBS206]

Check that the part where the CAS goes into isn't chewed out. It allows the CAS to flop around, and jumps timing up and down and causes mis fires mainly when attempting to hold revs constant.

[ECR 033]

Check that the part where the CAS goes into isn't chewed out. It allows the CAS to flop around, and jumps timing up and down and causes mis fires mainly when attempting to hold revs constant.

fits snug in there..plus its held in by the 3 bolts

[ECR 033]

fits snug in there..plus its held in by the 3 bolts

no error codes anymore... #55 (all good).

the misfire became less when i fixed an injector plug up (was still missing). after driving it a bit the miss gets worse and it starts to idle at 1500 rpm again. and goes up and down from 1400-1500.

given up.

[ECR 033]

no error codes anymore... #55 (all good).

the misfire became less when i fixed an injector plug up (was still missing). after driving it a bit the miss gets worse and it starts to idle at 1500 rpm again. and goes up and down from 1400-1500.

given up.

when cold it idles at 1100rpm and doesn't miss... then about 30-40 seconds later it starts...the hotter it gets th worse it gets..

(sounds like dodgey coil-packs but i've changed them and they wouldn't make the revs rise to 1500rpm at idle)

anymore ideas?

[bored33]

have you got a read out of your afm ratio?

[ECR 033]

have you got a read out of your afm ratio?

no. i do that how?..

[ECR 033]

no. i do that how?..

STILL HAVE A MISSFIRE!!!

I have now done:

new plugs (3 sets)

coilpacks (3 sets)

new coilpack wiring harness

New injectors

New Power FC

New Z32 AFM's

Crank angle sensor

[116.hks]

STILL HAVE A MISSFIRE!!!

I have now done:

new plugs (3 sets)

coilpacks (3 sets)

new coilpack wiring harness

New injectors

New Power FC

New Z32 AFM's

Crank angle sensor

just check to make sure you have no vacum leaks. its along shot but start from there. correct me if i'm wrong but didn't you have a problem a couple of weeks ago with it not starting?

[ECR 033]

just check to make sure you have no vacum leaks. its along shot but start from there. correct me if i'm wrong but didn't you have a problem a couple of weeks ago with it not starting?

i have checked for vaccume leaks and also replaced all hose clamps... i wouldn't have thought that would cause it to missfire...

yeah i had trouble with it starting... had no power to coilpacks..(all sorted)

[116.hks]

it can upset the afms if ya have vaccum leak creating a misfire and idling issues

[NYTSKY]

Take it to a trusted workshop.

[33gtst]

igniter module?

[ECR 033]

igniter module?

would any dodgy temprature sensors trigger it?

as i can start it fron dead cold and it runs perfect for around 6mins. then it starts to miss (igniter still cold at this point also)

[Adriano]

Sounds like a possible igniter module, make sure it has a good earth, and try a known good one.

[ECR 033]

To save reading previous posts... this is where i'm at.

I need some more ideas please...

Problem: Missfire

What happends: runs fine for about 5-6minutes (only when started from dead cold, once its a little warm it missfires every start), then starts to missfire, if you give it a few revs and let the throttle off it dies for a split second and then the revs go up to 2000rpm (at idle) then slowly come back down to 1200rpm. (missfire the whole time)

replaced:

Igniter pack

Coilpacks

Plugs

Fuel regulator

Injectors

AFM

Replaced all hose clamps

checked all possible air leaks.

new power fc

new o2 sensors

New temp sensors

New ignition wiring harness.

the engine is fresh and has had all new gaskets fitted etc.

Any more help with this would be great. I'n my head i feel its a vaccume leak issue still... what else would cause the problems mentioned?

Edited October 22, 2008 by BNR 032