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APR tune after battery removal

SnailPower

Drag Racing Champion
Hey guys, so I had my battery removed and put back this Sunday and I heard it removes your tunes back to stock mode. Is this true? I only ask because for 2 reasons. 1 is that, does this mean if you set the anti theft, someone only has to unplug your car battery to remove the anti theft feature? and 2, I'm having trouble realizing if I am still in my 93 octane mode or stock, lol.

I went thru the sequence and believe I set it back to 93 octane mode just to be safe but last time I gunned it in 2nd, my tires didn't spin like it normally did. Now I'm like, hmmm?

Any idea? Sorry if this is too noob a question but I'm still new on the tune aspects and this car in general, lol.

I actually never played with the tune features since getting the tune until now. Seemed simple enough...
 
Last edited:

PRND[S]

The Lame & The Ludicrous
You don't lose the tune, that can only be done by re-flashing the ECU.

What can happen is that the selected program changes to whatever happens to be in Slot #1 (if you have more than one program). For most people that will be Stock Mode, but that isn't universally true. The smart thing to do is to go through the program selection using the cruise control stalk and select the program appropriate for your fuel's octane rating.
 

Cryptic19111

Go Kart Champion
Yep, it may reset to slot#1, which is why I've always had them put the 93 tune first. Now I don't care anymore since I can see what it's in, and change it from my phone
 

SnailPower

Drag Racing Champion
Ok, yeah that's all I wanted to know. If the tune was reset. I know it can't lose the tune entirely as it's on the ECU unless it got reflashed but I wasn't sure if by disconnecting the battery and plugging it back in that you lost it's current setting.
Now what about anti theft? Would that also be lost with the disconnect?
 
Ok, yeah that's all I wanted to know. If the tune was reset. I know it can't lose the tune entirely as it's on the ECU unless it got reflashed but I wasn't sure if by disconnecting the battery and plugging it back in that you lost it's current setting.
Now what about anti theft? Would that also be lost with the disconnect?

The only thing that will happen if you disconnect or replace the battery is that the software will revert to the first program and typically engage anti-theft. So you will have to enter your code in order to start the car and to change the program.
 

cbenjes

Ready to race!
Happened to me once and when I finally realized it a month later and dialed in the 93 octane tune, it was like I got tuned all over again!
 

Michael58121

Go Kart Champion
so when battery is disconnected and connected it goes to slot#1?? i think i read it went to slot#2 if so then im not in 93oct
 

Thumper

Autocross Champion
The only thing that will happen if you disconnect or replace the battery is that the software will revert to the first program and typically engage anti-theft. So you will have to enter your code in order to start the car and to change the program.

YMMV

I had my battery die completely, sat without power for at least a week, swapped out for a AGM Optima and didn't have to do anything. My first slot is my 91 testpipe, and no lockout was engaged.
 

ShrekSquatch

Ready to race!
I just replaced my battery two weeks ago, and nothing changed for me. 93 octane tune is slot 3 for me, and I'm definitely not in stock mode... Battery was only disconnected for about 2 minutes though, maybe there's enough internal capacitance somewhere to keep it live for a couple of minutes.
 

D Darko

Ready to race!
I just replaced my battery two weeks ago, and nothing changed for me. 93 octane tune is slot 3 for me, and I'm definitely not in stock mode... Battery was only disconnected for about 2 minutes though, maybe there's enough internal capacitance somewhere to keep it live for a couple of minutes.

I experienced the same. No change.
 

GoodTimesIndeed

Go Kart Champion
I experienced the same. No change.

Same for me. Just had my battery out all day over the weekend while replacing front bushings (need to jack up side of motor to remove a bolt). Put everything back together, battery in, started up and still in 93 tune.
 
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