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Have written a few threads about this recently & Im sure some of you are sick of them but I need to try & find an answer... Had no car for months!

My RB25 is badly overfuelling on idle & all through rev-range. Injector pulse at idle is 7ms! Have no vacuum/IC leaks, have tried other AFMs & temp sensors, all with no luck... 1 interesting thing is I was told to unplug AFM & see what happened... While unplugged, the idle stopped hunting & exhaust stopped smoking, however you could smell it was still a bit rich. When I plugged AFM back in & went to rev engine, it was still in limp mode. I turned car off & on, same thing... Eventually with AFM plugged in I wiggled the wires & it came out of limp mode. It seems even moving where the AFM wiring meets the main loom has some effect on idle, (in & out of limp mode) but still nothing perfect. Does this give anyone any ideas? (bad earth from ECU to AFM, etc...) Really going crazy!

Any help appreciated

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I had a bad afm, the solder on the connections inside the afm from the plug had broken, another problem could be that you have a short in the plug its self, try another afm and see if it makes a difference.

have tried other AFMs & temp sensors, all with no luck...

How do you know the injector pulse time at idle?

Check that you have supply voltage (12V), continiuty of the signal line to the ECU, and check the ground(s).

How do you know the injector pulse time at idle?

Check that you have supply voltage (12V), continiuty of the signal line to the ECU, and check the ground(s).

Had short use of a scantool to check live data...

So supply voltage to ECU. Signal line from AFM to ECU? & does anyone know which pins in ECU are earths? Have a pin-out but unsure of accuracy...

How do you know the injector pulse time at idle?

Check that you have supply voltage (12V), continiuty of the signal line to the ECU, and check the ground(s).

Checked all this today, came back fine... Every test I do comes back fine although there is obviously something wrong...

Any chance ECU could be at fault? Or anyone have any other ideas?

Thats what Im starting to consider... Possibly a fault in the ECU itself. If it is thats fine, ill go get a Z32 ECU tuned to suit by Dr Drift or similar but if its not I dont have a clue what to try next

Thats what Im starting to consider... Possibly a fault in the ECU itself. If it is thats fine, ill go get a Z32 ECU tuned to suit by Dr Drift or similar but if its not I dont have a clue what to try next

If you in the frankston area i have an ecu here you can try to see if it is the ecu.

Thanks heaps mate but series 2 engine so possibly some difference in ECU... Seriously appreciated though

I believe S1 and S2 are the same, you can use the same model power fc on both, i believe the differences are outside the ecu, like the coils, S1 have an igniter for all 6 coils but S2 have an igniter on each coil, the ignition from the ecu is the same on both though, maybe do some searching and see what you can find, iys here if you need it.

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