|
It's worth noting that some ODB II hardware are actually read-only .. ie they dont even have the ability to write to the port. From the standpoint of an auto technician, it would not make much sense for the car to change the way it performs when the connector is plugged in since it would hinder the ability of the tech to diagnose a problem.
Notwithstanding, many cars do have special modes that hamper performance. I Know my car has an "Emissions Dyno Mode" where it will not rev above 6K RPM, and that mode is probably accessible via the diagnostic connector, but I imagine that you have to send some special commands down the wire to get a car to switch to some other diagnostic mode.
|