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hey guys,

i've had a safc in my car piggy back off the standard ecu for a year or so.

so 2 weeks ago i blew my turbo, the tune got a bit screwed up, but the standard ecu manage to sort the problem out it self. allowing the car to still be drivable, but just no boost and chews a bit more petrol.

due to a turbo upgrade, i purchased a apexi power fc, for rb25det.

ok i so took the standard ecu out, put the power fc in it's place, with the safc still piggy backing off the power fc. make sense? (safc and power fc running at the same time)

the car starts fine, and is drivable.

ok so i took the safc out today, and now the car wont start with the power fc by itself?, so i plug the standard ecu back in and the car starts again.

hmm so the question is:

why does the car not start with the power fc in just by itself? (the car would start for like 1 second and then stall.)

is there something wrong with the power fc? I initiated the power fc a few times (reset it)

when i go into the setting of the power fc, like 30% of it is in japanese, it that normal? and on the 'program version' menu, it said rb25det version...so it should the right power fc right..?

is the blown turbo causing the power fc make the car stalk?

im just worried the power fc isnt the right version for my car (r33 gtst)...but the serial does have 'Pfc rb25 9706' on it - theoretically if it's the wrong version it shouldn't allow the car to start even if it had a safc...

cheers guys...i know i asked like 20 question just then

steve

Edited by ztuned
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https://www.sau.com.au/forums/topic/221200-power-fc-safc-ecu-wtf/
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remove the safc

reset the powerfc

turn the car to ACC but dont start it

check the basic sensors, disable the boost kit

start car and perform self idle procedure

dont touch the throttle during the self idle, if you do, it will kill the idle program, which gives it the instant-stall affect when you start it

it sounds like you have two issues - 1 remove the safc, 2 do the self idle learn correctly (it sounds like you arent resettting it)

if you reset it correctly and start it without reading the instructions the engine check light will be on

yeah some of the menu's are in japanese and you have the correct version

the powerfc faq has all of this covered already- you should take a few moments to read it (its in my signature)

Just check the AFM wire is plugged together aswell. One end of it goes to the safc, then from the safc back to the other end which sends the modified signal to the ecu. If ya dont reconnect it in the middle u dont have an afm signal and ya car wont start.

Did the same thing accidently once :)

I had the same problem with an rb25 powerfc. I had 2 both with rb25 serial. I reset both of them. 1 would start and drive fine. The other would stall at idle but would drive if you keep the revs above 2000rpm but under 2000rpm it would just die. Even if you reset them to factory defualt they dont seem to work the same.

Edited by Brokenz

yep. for sure I would say it's a wiring problem. Power FCs seem to be much more sensitve to poor wiring and particularly to poor earth/poor batt volatage. check and double check all the wiring that the SAFC was involved with.

yep, it turns our it was the safc wiring from before. the blue/orange wire was cut...had to reconnect it and the car started after disabling the boost control kit :D thanks guys

i did the 30mins idle procedure. i could hear something weird when the air con is on, revs jumps a little bit every now on then..but i think thats normal. i can also hear a 'zap zap zap' noise every 30secs when the air con is on. it's not knocking, i check the knock sensor on the pfc.

every time i hear the zapping noise, the air con sensor flashes on the pfc.

i took a pic when the aircon is on:

and are the other black dots meant to be there? keeping in mind that my car has a blown turbo...so it's shit lol

DSC00514.jpg

this is covered in the PFC FAQ, its in my signature

you should read it...

http://paulr33.skylinesaustralia.com/docs/...erfc-faq.htm#20

Sensor Check

MAIN MENU, ETC, SENSOR SW / CHECK Look for any sensor names highlighted in BLACK background or any flashing sensors. Any highlighted in black indicates a problem. The engine check light will also stay on if any of the sensors aren't working (highlighted in black). This is not to be confused with the black DOT switch on / off sensors.

sensor-explain.jpg

so in your screenshot we can see

NTR is on - gearbox is in neutral

IGN is on - ignition is on

A/C is on - air con pump is on

ECC is on - main engine control

F/P is on - fuel pump control

FP1 is off - fuel pump not currently running

02H is on - 02 sensor heater control

ACR is on - air con something

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