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Trouble With Safc Ii

C yar

By C yar,
in Engines & Forced Induction

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C yar Veteran

C yar

Posted
Posted

ive had my safc II for about 8 months and my car ran great, no probs at all, then about 2 months ago, out of the blue, my car wouldnt idle at all.

sent my car back to the tune shop for a couple of days, after testing everything they could not fault anything. they had to adjust my fuel to +20% at ilde just to get it to idle then -20% off idle just so it was driveable....after a few more weeks my car went back to swap ecu's, no change, then we disconnected the safc and by-passed the wiring and car ran perfect.

any ideas on what when wrong with the safc and can they be repaired ?

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Sydneykid Grand Master

Sydneykid

Posted
Posted

I have never seen or heard of an SAFC having a localised problem, runs OK at some RPM's and not at others. They either work perfectly or fail completely (through incorrect wiring).

So I suspect outside factors;

My first point of call would be a dirty AFM. Try cleaning it with brake cleaner.

Second would be a bad connection between the SAFC and the ECU. Removing the SAFC means the connection is no longer there, so that's why it runs OK now. Idle is low voltage from the AFM (input), and a failing connection lowers the voltage some more, that's why adding 20% (increasing the output voltage) overcame the problem.

Lastly, I have seen a faulty alternator/battery (or a big stereo load) cause idling problems. As desribed above, the voltage gets too low at idle. Maybe check the alternator output and the battery just in case.

Hope that helps:cheers:

C yar Veteran

C yar

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thanks syd, i found it a pretty strange problem aswell... we did clean all connectors including tha afm so its not that... goode point about the alt voltage, i havnt checked that (will do ) as we have rewired the harness back to normal its a bit hard to do any more checks.... as to my idle problem, it wouldnt idle ie as if the ignition was turned off as the revs dropped down to 1100rpm.... even with the 20% adjustment it was by no means a good idle, very ruff when cold

i find it hard to understand why it ran great for 6 months then bag ... no go

i think i want to find someone with a safcII and plug mine in there car and see if she works, thart way i can sell the safc knowing its not faulty... anyone in perth want to help me ?

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