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Hey,

If I disconnect the battery, will it require a retune of the Apexi Power fc? or a dyno retune again? I think i heard it once before, but I am after clarification.

Im getting a bigger battery put in the car, and I need to know by Thursday lunchtime if im up for a lot more money than i set out :(

Admin, if this isnt the correct section please move me, as i was unsure of where to go.

Cheers,

Lachlan

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https://www.sau.com.au/forums/topic/351023-help-disconnect-battery-retune/
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Oh good. I was worried because im going on a 4 hour trip on friday and i didnt want to mess up my engine beforehand. Also not having the money for a retune is bad.

Thank you very much :)

My battery was too small for the amount of power my car needs, so i am getting a bigger one put in. I just didnt want to break any setup currently in the car as it would be too costly to put back.

Once again, thank you!

yep all apexi products i have seen have NVRAM to store settings even when powered off (even for a long time, ie months)

the RSM is even better by storing the top scores of each value when you key off, ie peak RPM and Speed etc

the powerfc doesnt keep top scores in NVRAM, only tune state and tune data

Why does this question always surface?

from Wiki:

Non-volatile memory, nonvolatile memory, NVM or non-volatile storage, in the most basic sense, is computer memory that can retain the stored information even when not powered. Examples of non-volatile memory include read-only memory, flash memory, most types of magnetic computer storage devices (e.g. hard disks, floppy disks, and magnetic tape), optical discs, and early computer storage methods such as paper tape and punched cards.

bring back the ol 5.25" inch floppies, 360k

awesome

an unofficial hack was you could flip them over, cup the other side out of the floppy and use it as a double sided double density disk, 720k phwoar!

Generally NO but it can happen, but it is very rare i have had to go out to a few panel shops over the years and reload tunes. i think it is more a results of a quick backwards jumper battery short :)

yeah it shouldn't drop the tune. but one thing I'd suggest anyway is ask your tuner for a copy of your tune to be emailed to you. that way should you ever for some reason loose your tune you can just get it reloaded with datalogit and a laptop. 5 mins work.

  • 1 month later...

hi all, im a newbie to powerfc and currently doing a lot of reading in paulr33 powerfc faq

my car is a 96 r33 with top mount 3076, injector, z32 afm, pfc tuned by previous owner

yesterday i disconnectedmy battery and unplug my powerfc to change boost controller from greddy to Blitz id...

and when i put every thing back, i start the car and it starts but immediately stall..

i read the faq, i believe i need to enter the injector and airflow meter setting etc

now before i go and do all that, i just need to confirm some questions:

1.) have i lost my previous tune?

2.) in my situation now, should i enter injector and afm setting? or try to reload previous tune?

3.) how do i find my previous tune in pfc and load it??

cheers all

Edited by julius_son

no disconnecting the battery or even the ecu will not (well should not) lose the tune. the tune is stored in solid state memory. disconnecting power won't erase it.

if the tune really is gone then just punching in injector numbers and the AFM type is not going to help at all. it will need a complete re-tune. or, you'll need to get the old tune (only possible if the tuner kept a copy on his laptop and is willing to give it to you) and have it relaoded onto the power FC using datalogit (or similar) and a laptop.

my guess is you have done something wrong with the EBC install. double check there is no loose vacuum lines etc.

Thanks Baron,

The car starts after i install the Blitz EBC and just before i realise that i have to connect a wire to the speed sensor,

then i disconnect the battery and unplug pfc and wire up to wire 53

hook everything back, and then it starts and stall straight away.

i use meter to confirm there is power to pfc...

On this ground i believe wirings are ok and i probly have to check all the vacumm hoses like you said!! i mite knock some out when putting everything back...

thanks Baron again, just realise i havent double check the vacumm hose and blame on the pfc lol, will let you kno

If you haven't turned the boost control setting off on the power fc your car won't start... ( should only be on if you have a power fc boost control kit installed and connected) is this your problem?

hmmm im in perth

and i just look at my car again, checked all vacumm hoses and all are good

and i did what Don dada said and go into setting>airflow, there are 5 lists and the VG30 is not highlighted...

i also did sensor check in SENSOR SW, the "bost" is highlighted and "AF" also highlighted!!!

so i guess there something wrong with airflow??

is late now, will check the airflow wiring tommorow after work....

if anyone have same problem, give me some headsup, like where to look at first...

most likely i will take it to a tuner if i still cannot fix

thanks all for advices

where bouts in perth are you? i'm NOR and can get it driveable for you until you sort out another tune (sounds like it has reset, as your afm and boost control settings have changed). PM me if your interested

where bouts in perth are you? i'm NOR and can get it driveable for you until you sort out another tune (sounds like it has reset, as your afm and boost control settings have changed). PM me if your interested

pmed!!!

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