I had my PCM custom tuned by Ion and it worked great, but the other day my alarm wouldn't stop going off so my mom decided to unhook the battery... it was unhooked for about 7-8 hours while I was at work.. And after I plugged it back in, it's like.. the PCM went back to default and lost the tuning cause the car likes to do a nose dive at idle like the idle was set back to stock. I was curious if that is possible or if the PCM tuning is an actual burn into the computer.

 

It's a permanent program, so disconnecting the battery won't erase it. It may take a few drive cycles for it to "relearn", so give it a bit more time.

 

Wow.. quick reply lol thanks Madwolf, btw putting in an AC compressor sucks lol took me, never have done one before, 4 hours last night and lots of banged up knuckles and aggitation.

 

That's why I took mine off.

 

Texas heat + Black car - AC = unhappy GF