Help...rb25Det Issue

[gt35r]

My series 1 r33 skyline with series 1 rb25det is got a problem. It idled rough on a cold start untill I give it some throttle. And randomly cuts out when driving around 2500-3000 rpm. It also stalled while idling last night. I've cleaned the aac valve and air flow meter. I've changed the fuel filter, air filter, o2 sensor, coil packs and put iridium plugs in it and it is still doing it. The cutting out is random as in, one day it won't do it, next day it will and it varies from one quick cut out to 5 or 6 times in a couple of minutes. It is similar to when a car runs out of fuel. Any help would be appreciated.

[DVS JEZ]

Try another afm

[hop1308]

same thing happened to my old 33. couldn't figure out what it was n sold it.

[gt35r]

Try another afm

Could the afm be dieing in the arse causing the engine to stall

[DVS JEZ]

Yes. Very common too

[gt35r]

Got a hold of another afm. Will give it a try and post up the outcome

[DVS JEZ]

Kool

[gt35r]

The afm I got was 70mm off gtr and not 80mm for a 25. Car didn't stall while idling and didn't cut out like normal but surged when accelerating hard so the problem could be afm but yet to justify that when I get the proper one. I'm getting a z32 soon but have read that I can't connect it untill im ready to put my pfc in and get it tuned.

[gt35r]

Will series 2 afm work on series 1?

[DVS JEZ]

Unfortunatley not. Different plug or a start and different VQ map needed in ecu.

[gt35r]

Ok so I got a hold of a new afm to suit. I plugged it in and the car was idling rough. Drove ok but idled rough for a bit, seemed to idle ok after a bit of a drive and warm. I'm yet to drive the car today but Could it be cause the ecu needs to readjust to suit.

[DVS JEZ]

Is it the correct afm?

[gt35r]

The part number on it says its the same as the old one I had and the guy at jap autos says its the right one. It not a jecs or Nissan one, its just a aftermarket one but is brand new. I didn't want to fork out for a jecs when I am putting a z32 on it in a few weeks when I get my new turbo.

[willzgtst]

this happened to me also, i replaced my air flow meter, it took about 20 mins to really change anything as the car was still running wierd, after it warmed up and started rolling on the freeway , suburban roads and stuff, i realised i had no power cuts or engine stalls, so it was my afm, Most of the idle and stalls point to AFM, i found one cheap, and genuine , look around!

BTW just fyi, aftermarket ones are CRAP, mate had one on his r33 and it didnt last very long and caused him issues, couldnt start the car and kept dieing on him all the time.

Edited September 27, 2012 by willzgtst

[gt35r]

Car seems to be running better now but occasionally has a bit of a rough idle and mainly when cold. Also get a bit of a pop/backfire on down shift and in between gear changes when getting into it a bit. Could this be because its an aftermarket afm?

[DVS JEZ]

I wasted 2hrs on the dyno today to do what is normally a straightforward tune.

Then i removed the "z32 afm" brand new from ebay and fitted a genuine z32 2nd hand from one of my cars, tuned up perfectly after that.

DO NOT USE COPY AFM's. This is the 2nd time i have wasted time due to them.

Buy a genuine only