w204nyc

I had my car at the dealership for a CEL and it was a O2 Sensor again. A guy there was telling me they usually reset ECU's after they put new sensors in. Is it possible that they reset my ECU? My car feels slow as ****!

CarHopper

Were you tuned before? Because they in theory could but I doubt it would remap the whole thing to lose any type of tune...

maybe?

w204nyc

Yes OE Tune!

BAD430BENZ

look it up in the search bar.....they can flash you back to oem . if you don't have a mod friendly dealer , then you need to get a handheld device for your tunes or get a spare ECU

Fung63

or just get oe to reflash your tune.

w204nyc

Damn they probably did reset it. I will speak to OE!

Mort

If they reset the ECU it should say so on the repair order. Call them and ask if you are not sure.

SoFlaC63

ehhhhh be skeptical of this. When your car has a check engine code, and they do the repair all they do is clear the codes. Basically pulling a battery cable to clear the computers memory. Obviously they use STAR diag. but it does the same. I honestly don't even know if they can see if its been flashed, possibly but i dont know how in-depth STAR diag. is. We use many scanners at our shop, none of which could remap or edit computer files. It will relearn everything and you would NOT lose your tune after clearing the codes.

On the other hand if they reflashed your computer, i.e. software update then yes, its possible. I wouldn't be under the assumption that they would let you know there was a software update. Plus a flash would take much longer than a simple wipe of codes. Hence a bigger charge for such a thing. (assuming your not under warranty)