Originally Posted by GaryTucker
What everyone fails to think about is what happens with a catastrophic failure? Sure you can slap that old ECM in...but if it isn't reading anything near what could have caused your major failure...then do you think the dealer will buy it? Some items have to have a run cycle to reset...so that ECM that's been on the shelf for 6 months still shows something out of kilter for the situation your car is in.
The factory parameters are lost and the monitors are reset to "not ready" when the ECM looses power for any reason. So if you install an unplugged ECM it will definitely not show any believable data. So the thing to do in this instance is to run the car battery down with the flashers and have the car towed in with the battery down and the flashers on, the dealer will be none the wiser.