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Hi guys

3-4 weeks ago my car stopped at traffic lights and didn't start up.....then we have replaced the fuel pump , car was fine for week. but most of the time RPM playing up (slight play). now sometimes my car stalls , RPM plays while driving (dropping below 5).., dropping power ,cannot start without accelerating. I have replaced the idle controller unit (used) and AFM (used) but still doing the same. What do you guys think.......

Basic computer reading are OK (before replacing AFM and Idle controller)......i have reset the ECU as well..........What should i do now? is there any good testers to fault find? how do i fault find my new fuel pump? is the AFM and idle controller of S2 is differ from S1?

Thanks in advance

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Can you try swap ECU's with somebody? I had all world of trouble with mine when I bought it yet it turned out to be a dry joint in the ECU.

I would have never known till swapping it to another just to test. This is by no means me trying to tell you that you have the same problem, merely advising you may want to try.

GL

Don't mean to hi-jack. But sometimes when I'm slowing down and go into neutral the RPM will drop to about 500rpm heaps quick then go back up to around 700rpm... do I have the same problem? It also goes funny when in neutral and I'm going slow and turning (for instance, into a driveway). NFI what turning the steering wheel has to do with the idle but it definitely makes a difference. =\

have u guys tryed adjusting ur idle? 1st try with the screw on the aac valve if that doesnt help dissconnect the battery and do it the long way - theres an adjuster on the ecu aswell as the screw on the aac valve - theres a DIY guide on here.

to the OP - if your idle is correct or higher then it should be then this probaby wont help you

RB25PWR - when u move the steering wheel on the spot it'll put a bit of load on the engine - the aac valve is supposed to raise the revs a bit when this happens. sometimes it wont lift the revs and instead it'll drop the revs if the idle isnt set perfectly so maybe try adjusting it also.

what it should do:

when its cold - about 1400rpm

running temp - about 700rpm

when i turn the a/c on - revs should raise about 100rpm

when i steer on the spot - revs should bump up about 100rpm for a second then go down

also note - when its cold my revs are always around 1400 and as soon as its warm there at 700, if its behaving weird like idling high when its warm and sometimes low when its cold then u gotta problem - i would start with cleaning the aac valve, checking the resistance of the coils (im not sure what they should be - im sure some research will find the answer) and resetting the idle.

as said before changing the ecu probably is a good idea, i mean theres plenty around so it shouldnt be hard to source one, and also if something isnt right in the ecu then literally no matter what u do with all the sensors and switches it wont make a difference

Edited by jimmys-33T

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