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Hi guys

Need some help/advice with my r33 gtst.

Basicly my AFM's keep dying after few hours of driving. I had 3 pink label afm's put 1 in, it would run good for a few hours then die. Drove from morley to birba lake put the car on the dyno for a run and the car made 220bhp with the car f*king up. Switched the afm again put the car on the dyno and pulled 278bhp. Cars mostly stock basic mods fmic exhaust and 10psi of boost. AFR on first bad run was around 10-10.5. AFR on good run was up around 12, All afms were just standard pink labels.

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https://www.sau.com.au/forums/topic/389097-r33-air-flow-meter-problems/
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Are you sure its not a connection or something else?

1 not working - yep

2 not working - you got poor luck.

My experiance is that the either work or they dont (one the car is warm) so even stranger that its ok for a few hours then goes bad. Happy to be corrected on that.

Find someone that has a working unit, try it and if it still happens you know it something else causing the problem.

Cool Story:Personally I have had them stuff up too. It still worked unless u put your foot down and then would read so incorrectly it caused a boost cut, extremely wide range of idles depending on weather or car would be lacking in power for no apparent reason and lurch! Purchased a second hand unit from here.. guess what.. just as faulty. Purchased a unit from JPC, problem solved and never returned.

Fix:

1 - Check your wiring for the AFM is not shorting out or is damaged between your ecu and afm. Run a direct temporary wire (if your ok with wiring) to test this.

2 - Try an AFM with a guarantee that it works!

  • 10 months later...

still COULD be coilpacks, have them bench tested before you rule them out. especially if they're chinese copies, normally splitfires are pretty good though

ive personally had a brand new aftermarket coilpack fail, so it is possilble

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