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Ok can someone clear this up for me... I have an r33 gts-t with a few bolton's as such she runs pretty rich.

Solution: went and got an SAFC II, had it fitted and tuned... all good power band feels a lot nicer and fuel economy goes up a little...

Problem: Battery goes dead and the car feels nothing like it used to... Confirmed that the settings in the SAFC have held so it's not like it has reset it's self

Ok so my questions is this... when you disconnect your battery and replug it in after draining any residual power out of the car the ecu resets it's self back to bog stock settings as such when you crank the car over it runs a little off eg idle hunts a bit etc then after a minute or two it feels normal again... I have always been told that these ECU's are a self learning ecu but that they don’t actually store any settings... eg on long trips it will adjust it for better fuel economy and if you strap it the car will get used to be revving harder and using more fuel etc...

I had my safc stolen a while back so it has been running on the standard ecu. I am just worried that when I hook the new one up and get it tuned it will be fine again till the battery dies... should I disconnect the battery first then get them to tune my SAFC... or alternatively should I just wack it on get it tuned... then disconnect the battery, reconnect it and whack it back on the dyno to confirm if my suspicions are correct.

Any comments including rage are welcome :)

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the safc settings are stored in nvram so it wont loose them when its lost power. the ecu will perform a quick self init / self learn to maintain stable idle but its far from "retune feature"

replaced my dead battery, was going all the time.

hasnt affected the tune of the safc/sitc combo.

for a short while it seems off, but the 'feel' of the power delivery comes back. :laugh:

Don't forget that if your battery goes flat and the ecu does get reset, when it relearns - it'll be learning according to what the SAFC is feeding it e.g. modified values, not sure how this will affect it, but could be good just to get the tune checked..

Don't forget that if your battery goes flat and the ecu does get reset, when it relearns - it'll be learning according to what the SAFC is feeding it e.g. modified values, not sure how this will affect it, but could be good just to get the tune checked..

Yeah, might be an idea to reset the ECU with the SAFC disconnected and see how it goes.

See that's my thoughts. When it's tuned the first time it has done based on whatever the stock ecu has got in it's mind as default settings. The SAFC then just tricks the ecu into thinking what it wants... So if the battery is flat/disconnected then reconnected it's not going to know what it's original values were it will be taking what the SAFC was tuned with... i dont know maybe this is only making sence in my head as i can't find the correct words to type out :)

Don't forget that if your battery goes flat and the ecu does get reset, when it relearns - it'll be learning according to what the SAFC is feeding it e.g. modified values, not sure how this will affect it, but could be good just to get the tune checked..

the standard ecu has stock values but has the ability to learn if you've changed airflow etc no matter what you had before. the values change but not by much, it'll still put out the same values of airflow, timing etc after a battery change.

the safc stores all tuned data in its memory.

my car had no power into it for 6 months (rebuild) and when i put it back together it was exactly how i left it.

its nothing to worry about.

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