Personally I wouldn't buy a "used tuner". Depends on the brand of tuner, wouldn't be good business for a tuner programmer to allow unlimited programming from their device to umpteen numbers of vehicles. Know your seller. I wouldn't want to get stuck with an expensive handheld paperweight.
You wouldn't be able to tell until you tried to hook it up..if its an edge you can call them and for a small fee they will give you a hot unlock code so its useable again Sent from my DROID2 using Tapatalk
Why not if you know that it isn't VIN locked? OP, you can usually send them in to have them unlocked but it's going to cost you enough on top of the purchase price that you could have bought a brand new one to begin with.
My friend and I bought two seperate Bully Dog 4 bank chips. His is a 2003 PSD and mine a 2000. Mine I can switch while running to a different program mode, on his if he switched programs while running it shuts off the truck, he has to start the truck in the mode he wants first. He had his truck at a Ford Dealership for service and they reflashed his ECU-PCM, now his chip won't work at all on the new flash. He won't call Bully or their reps to get a new code 'cause he said he paid once for it and he isn't gonna pay more again for the same thing to happen again.
x2. As long as the previous owner puts it back to stock, you'll be fine. Also, if you're looking at an Edge Evo/PHP Gryphon, the unlock fee is $75.