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any of you guys experienced stalling once the SAFC is installed? i havent tuned it yet but set sensor to now set to 4 in 4 out as stated in the manual for a R33 GTST (HW-4). When the car is cold and and i try to accelerate, its like not pumping enough fuel and the car feels it going to stall? this happen straight away after the SAFC installed. i was thinking the A/F has been adjusted now? but i havent changed any settings besides the sensor type 4 in 4 out. I have already initilized the unit so now back to default settings.

Checked in:

Menu:

=====

1: Monitor

2: Setting

3: Etc..

Selecting Setting ----> Dec. - Air --->

it reads:

Thr : **** %

Ne1 : 10.0 %

Ne2 : 10.0 %

Is this right? that Thr : **** % ?????

If one of you guys can just turn on your car and go into settings --> sensor check --> see if it is set like the above and get back to me would help me heaps.

and:

3: Etc.. ---->

Sensor Check --->

Reads:

In-1 : 1.02v

In-2 : 0.03v

Thrt : 0.475v

Is the voltage ok? Using a stock A/F sensor.

Checked all my wires, they seem fine:

Red Wire = Power

Green Wire = PRM Signal

Gray Wire = Throttle Signal

Brown & Black Wire = Ground (Brown closest to ECU)

Yellow Wire = One end Connected to A/F Senor (close to ECU)

White Wire = Other end Connected to A/F Sensor

I also have the Apexi turbo timer. When check the A/F on that unit during decelerating, it jumps from a steady 14.5 all the way to 20??? Is this right?

Car hasnt been boosted so running 7psi stock using a stock BOV .Waiting to get it boosted before tuning the SAFC..

Already checked www.apexi.com documents there are kind of hard to understand... :(

Cheers

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does your a/f jump around on when u accelarate? when u back off its normal to jump around a bit .That throttle sensor is cool just means ur not using the dec feature ,which is bull shit anyway.Check that your lo throttle map is on 0% from 1k-8k if it is then triple check your wiring mainly your a/f signal.If its second hand then it could be faulty ,i bought a 2nd hand safc that just wouldnt let the car idle proply ,got another 1 hooked up the same and worked pefectly

Thanks for your help once again Bo0sT_JuNkY :( my a/f stays the same when i accelerate only jumps to like 20 (from the turbo timer) when decellerating. Just checked low and high trottle map all set to 0% from 1000 - 7000prm. Too cold and dark right now to check the wiring.. will do it first thing tomorrow..

Thanks once again dude..

btw:

Does your Dec. - Air -- reads

Thr : **** %

Ne1 : 10.0 %

Ne2 : 10.0 %

?

Is Thrt : 0.475v too low for throttle voltage?

THR is your throttle.. if you monitor the THR, when you squirt the accelerator it should show you how much you pressed it (e.g. 50% half to the floor, etc). Likewise "sensor check" should show the voltage for THR changing when you do that.

Sounds like you missed a line to the ECU ? if its reading **** it probably means it can't read the THR reading, and hence having problems.

I'd let u check all mine out but don't have my car atm..

for Dec-Air : from memory the "Thr" setting is the amount of throttle where the SAFC will start to compensate and try to stop stalling. i think i set mine to something very small like 2-3%. ie if you have less than 2% throttle pedal pushed down it will compansate.

the ne settings refer to the amount of extra fuel the SAFC will dump into the engine at that rpm to stop it stalling. i think mine are at about 4-5% for ne1 and 3% for ne2, bearing in mind that the settings on the fuel graph for low throttle are around -7% for those points

does that make sense??

without the Dec_air set up, my car stalls all the time when pulling up to lights/clutch in, worse +++ when the engine is cold.

try those settings and see how you go.

What does Ne1 and Ne2 actually mean on the Dec Air setting?

Edit: I know they mean +fuel, but what's the difference between the 2? And if it constantly adds in fuel at idle, wouldn't it be the same thing as setting the lowest throttle point higher?

Originally posted by predator666

THR is your throttle.. if you monitor the THR, when you squirt the accelerator it should show you how much you pressed it (e.g. 50% half to the floor, etc). Likewise "sensor check" should show the voltage for THR changing when you do that.  

Sounds like you missed a line to the ECU ? if its reading **** it probably means it can't read the THR reading, and hence having problems.

I'd let u check all mine out but don't have my car atm..

im afraid of that :D . im 100% sure all the wiring is good, so on your safc it does read **** in the Dec. - Air -- Thrl:??

will recheck the cables again.... ohh noo.. thanks for your great help once again gord! :D

Originally posted by Beeble

for Dec-Air  :    from memory the "Thr" setting is the amount of throttle where the SAFC will start to compensate and try to stop stalling. i think i set mine to something very small like 2-3%. ie if you have less than 2% throttle pedal pushed down it will compansate.

the ne settings refer to the amount of extra fuel the SAFC will dump into the engine at that rpm to stop it stalling.  i think mine are at about 4-5% for ne1 and 3% for ne2, bearing in mind that the settings on the fuel graph for low throttle are around -7% for those points

does that make sense??

without the Dec_air set up, my car stalls all the time when pulling up to lights/clutch in, worse +++ when the engine is cold.

try those settings and see how you go.

Thanks for your feedback and help Beeble. been great help. :D

Someoen should start designing a virtual SAFC website !.. heyy good idea i might create one so people can start playing with it online? as in take screen shots of the menu's and u can flick through it and stuff without actually doing it on your car as you dont wanna stuff it up..

I experimented with my Dec Air settings. They were set to **** 10% 10%, and I changed them to roughly 5% 5% 5% and now it seems to stall easier. I don't know if **** means the function is switched off entirely or if it means 0% (I didn't take note if the first step was 0.1% or 0.0%) but either way it was better the way it used to be. But not much coz it stalls either way.

I also took note of how much throttle was on percentage-wise when my foot was *just* touching it. It came up around 6-7%, so I think if you were going to set the Dec Air position to be 5% you may as well set it to 0% (or vice versa).

Hehe I just looked over what I wrote and it looks like I've been censored :D

lol JimX. Thanks for your info too dude.

I experimented with my Dec Air settings. They were set to **** 10% 10%, and I changed them to roughly 5% 5% 5% and now it seems to stall easier.

have you got afm BOV?

From the Apexi SAFC Manual page 22, it reads:

When the Thr reads **** the deceleration parameter is not functional???? how can it be not functional? that i dont get.

Anyone else experience this too?

Yes, I have an a/m bov.

Hmm, so **** means it's been doing nothing all this time. I'll try 5% 10% 10% and see what happens. I think it needs to be a bit more than 5% extra fuel, because when I'm trying to stop it stalling myself, I need to put my foot on the throttle a little more than the 6-7% I quoted earlier. Maybe 15 or 20% then.

I get the feeling that all I'm going to accomplish is waste more fuel but keep stalling anyway :D

Thats soo weird JimX. Anyway i rewired the throttle wire once again , resetted my ECU, hooked the trottle position wire back in place and now in Dec. - Air -- Thrl NE1: 5% and NE2: 5%???

so the values have changed from 10% in NE1 & NE2 down to 5% and all i did was rewiring it.

kinda weird.. anyone experience this?

I tried 5% 15% 7% and it seemed better to begin with, but soon started stalling again. It's almost as if you can tune it to not stall, but the ECU's learning mode decides that stalling is better and starts stalling again.

Does anyone know if a PowerFC definitely fixes this or do you still need an extra idle controller (like the HKS one).

Pushead, I haven't written down the current settings yet (too lazy), but I've got the old ones after the first tune. The only difference between old and new are catering for a front-facing plenum and bigger front-mount intercooler. I wouldn't advise using these settings directly as a base level, except for maybe the Lo/Hi throttle settings. If you do I won't be responsible for blowing your engine up :P

Apexi S-AFC settings:

Lo: %

1000 0

2000 +3

3000 +5

4000 +1

5000 -4

6000 -2

7000 0

8000 0

Hi: %

1000 0

2000 +3

3000 0

4000 -8

5000 -13

6000 -9

7000 -2

8000 -2

Throttle position:

Lo: 45%

Hi: 46%

Dec.Air:

Thr: 5%

Ne 1: 15%

Ne 2: 7.5%

Oh, the car seems to be not stalling again. It's going through some phases, and I hope it settles on not stalling :) It's come close to stalling but didn't do it at all tonight. So I think the above Dec. Air settings are a good baseline to start with.

pushead dont copy other peoples safc settings.

also turn the dec air feature off, it has never worked properly on any car i have seen. Leave it on 0.

your car should have any problems is all the setting on the afc are 0, as it will be like the safc isent even there

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