Apexi Afc Neo (safc) Tuning Issues...

[SKiT_R31]

Hey All,

I've got an R33 RB25DE+T (Stock RB25DET ECU and Injectors), with an AFC Neo piggy back and a wideband O2 Air/Fuel ratio + RPM datalogger (innovate).

I've had the car on the dyno before so i knew the fuel mixtures were way out, on my first run everything was spot on, the AFR's at RPM points match the dyno plot perfectly.

At light throttle with my cars lambda sensor disconnected the car ran at 10:1 AFR, which was fine - I was able to lean this to the 12's no issues whatsoever (took -20% on the AFC), this was my practice and everything was fine. So now I started to work on my massive lean spot at WOT (car lean spikes to 16:1 at 3000rpm), kept adding fuel up to +50% but it didn’t make any difference... Moving on from this I tried to adjust my rich spot up top (10:1 AFR from 5000 to 7000rpm) no matter how much fuel i pulled out of it, it just didn’t make any difference to fuel mixtures or the pull of the car. The AFC shows the correction (in the monitor mode), but it just doesn’t do anything... It's like the ecu is RPM mapped at those points... The more i lowered the boost (its at 10psi), the better the lean spike looked (~ 8psi brought it to 14:1).

Any ideas? The AFM in and out are both set to 1 is this correct? All wiring is perfect.

Cheers for any info, don’t tell me to take it to a tuner.

[STATUS]

you physically are out of fuel, pump most likely.

[SKiT_R31]

you physically are out of fuel, pump most likely.

This did cross my mind, but it clears up top, to the point where it gets excessively rich...

[SKiT_R31]

I think I've found the issue (though not sure if it would cause my symptoms...?); I installed this based off this guide:

http://www.skylinesaustralia.com/forums/Sa...3-G-t85232.html

Where is says set AFM IN and AFM OUT both to 1

But reading here: (Page 24)

http://www.scribd.com/doc/19576441/Apexi-I...-Wiring-Diagram

It says set both to 4.

I'm not sure if the AFC is different, or if it is wrong, or even if it will make any difference - I'll have to wait until I get home tonight.

Please still post if you have any other insights...

[jjskyline79]

Have you made sure you've set your throttle position as you have to calibrate it for your car? As it sounds like the % for the hi map is screwed up. Should be around 35% that it switches

But yes iir it should be set at 4 both in and out.

Edited July 6, 2010 by jjskyline79

[SKiT_R31]

Yeah that’s set right, low throttle comes in at 0% and high throttle is at 40%.

I've tried moving the threshold higher to run of low throttle maps, but it doesn’t make a difference. Regardless it runs increasingly rich until around 45% throttle, then it leans right out.

[SKiT_R31]

Setting it to 4 & 4 didn’t make a difference. I randomly set one to 1 and one to 4 to test it and the car spluttered like expected, so it is working...

Here's a picture of my wideband log, RPM vs AFR, you can see the lean spot which i am trying to iron out....

[jjskyline79]

Could it be beyond what the Neo can do with your current tune/mods

[SKiT_R31]

I really hope not, can’t really fork out for full management. Everything is fine I just need to correct these fuel mixtures.

There must be a reason for this issue... Its not like I can’t adjust it any further, its simply just not making any difference to mixtures (even if I +50% it).

[SKiT_R31]

Problem solved, looks like it was just my water+meth setup confusing things. Had to wind a little boost out of it though but these are the results.