S15 afc neo issue - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

Flex2003 · 10-10-2014, 03:34 PM

Having a issue with what seems fuel cut or some type of limiter.
In 3rd gear 4000-4500 12-14psi 12 afr thens cuts fuel seems like

Cars 99 s15 stock turbo and injectors. Turboback, fmic and piping, non recric bov , aem wideband,greddy boost controller,255 fuel pump, z32 fuel filter. Never had this issue before installed neo this weekend. Afc neo with boomslang harness. 5/5 maf settings.

jr_ss · 10-10-2014, 05:39 PM

The SAFC is your issue... Get rid of it and buy a Rom tune or tuneable ECU if you plan on modifying and retaining any reliability.

Kingtal0n · 10-12-2014, 03:39 AM

You've run out of maf voltage. the safc is able to adjust fuel up by adding maf voltage. If you max the maf voltage, the ECU cuts fuel.

You need a stand-alone and a larger maf, and/or, larger injectors. the larger injectors will lower the maf voltage that the ECU will see, thereby side stepping your current issue (fuel cut).

However, by lowering maf voltage to avoid the fuel cut, you will be telling the ECU that the engine is under less load, and to add more timing.

enough timing to ruin your engine, thereby giving the safc the bad reputation it deserves.

10-10-2014, 03:34 PM	#1
Flex2003 Join Date: Aug 2014 Location: Edmonton Posts: 5 Trader Rating: (0) Feedback Score: 0 reviews	S15 afc neo issue Having a issue with what seems fuel cut or some type of limiter. In 3rd gear 4000-4500 12-14psi 12 afr thens cuts fuel seems like Cars 99 s15 stock turbo and injectors. Turboback, fmic and piping, non recric bov , aem wideband,greddy boost controller,255 fuel pump, z32 fuel filter. Never had this issue before installed neo this weekend. Afc neo with boomslang harness. 5/5 maf settings.

10-10-2014, 05:39 PM	#2
jr_ss Post Whore! Join Date: Dec 2005 Location: Pa Posts: 6,413 Trader Rating: (35) Feedback Score: 35 reviews	The SAFC is your issue... Get rid of it and buy a Rom tune or tuneable ECU if you plan on modifying and retaining any reliability. __________________ My SR20VET Does your VTC gear rattle in your S14/15 SR? PM me.

10-12-2014, 03:39 AM	#3
Kingtal0n Post Whore! Join Date: Jul 2005 Location: South Florida Age: 41 Posts: 4,829 Trader Rating: (17) Feedback Score: 17 reviews	You've run out of maf voltage. the safc is able to adjust fuel up by adding maf voltage. If you max the maf voltage, the ECU cuts fuel. You need a stand-alone and a larger maf, and/or, larger injectors. the larger injectors will lower the maf voltage that the ECU will see, thereby side stepping your current issue (fuel cut). However, by lowering maf voltage to avoid the fuel cut, you will be telling the ECU that the engine is under less load, and to add more timing. enough timing to ruin your engine, thereby giving the safc the bad reputation it deserves. __________________ 5.3/4l80e/turbo 240sx playthrough: tinyurl.com/4l80er