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Hiya,

While putting my car on the dyno the other day, I got them to test the air flow ratios, much to my suprise it's running a bit on the lean side of things (running 98 octane fuel with octane booster).

I know that running too lean can cause detonation, but thats about where my knowledge of the subject ends, so I was hoping someone could shead some light on the subject for me please.

My question is what can I do to get it fueling right. Any one have any ideas where I should start to fix this potential nightmare.

your advice would be appreciated, thanks

Rachael

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Before spending out $$$ on SAFC then finding out changing the setting on SAFC doesn't do anything to improve situation, maybe you should check first whether your fuel pump is heatlhy or about to die, or your injectors are dirty and not flowing enough fuel....

If they're both healthy, go buy SAFC and tune it to richen your A/F at desired rev points.

Rachael - what mods have you got?

I'd be checking anything that feed fuel to the engine, pump, filter, injectors, etc. And I'd be checking anything that measures air flow/volume/pressure as well like the AFM before blowing money on a SAFC. Maybe an ECU reset might help too.

cheers :stupid:

Thanks for the speedy replies guys,

My mods are K&N panel filter, extractors, and 2 1/2" exhaust. The fuel filter was changed 12,000km ago, I generaly change it every 15,000 km. I run injector cleaner through the fuel every few tanks, and the ECU was reset 1000km ago. To be honest I'm a service nut.:crazy:

Righto, the AFM sounds like a good place to start, is it something that can be tested a home or will it need to be done by a mechanic?

thanks

Rach

After talking to a mechanic today, he suggested a fuel pressure regulator would be the best thing to do for a quick fix.

As checking the rest of the system is pretty much a process of deduction, replacing the parts untill the problrm causing culpret is found. (me thinks it's going to get very expensive):D

i hate that

i have to sell all my goodies that will be no use to me with my new engine otherwise ill never even get started. chance are ill sell the goodstuff and never get round to doing the engine and be driving round in nothing more then i a riced up line :D hopefully that wont happen.

AFM = Air Flow Meter

S-AFC = an apexi computer "Super Air Flow Controller" it intercepts the signals from the airflow meter and tricks ur computer into thinking it has either more or less air, givving u the ability to adjust how much fuel the computer gives ur car in return.

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