Using programmer on a flashed ecm?
 

Anyone know if its ok to use a programmer on a flashed ecm? I picked up a Hypertech and want to use it to change my fan turn on temps. Just curious if there would be any issues since the ecm has been flashed, vats/rear O2's, the usual.

Thanks.

some programmers copy whatever file is in the ecm as the stock file, and then you mod from there. That wouldn't be an issue. I am not sure that ALL do that, so if they re-flash the entire tune with whatever is in the programmer you'd lose your changes.

Who did the original tune? For something so simple as that, most tuners will simply do it and not charge you or charge you so little that it's not worth buying a hypertech. Also, what are the turn on temps? I find a lot of people want a turn on temp set at an unnecessary temp. To answer your question though, I wouldn't do it. I don't like the hand helds because you don't know exactly what it's doing.