If you're OBD2, you're going to throw a code with a test pipe. The guys at NTPOG made a "work around" that resets the ECU when you shut it off every time. I'm just not sure if it throws a code 20 minutes later or not.
For example, you can unhook the hose for your IAB's on your IM and it'll sputter a bit at idle, but supposedly help if you're running hard, at the drag strip or something, but after a few minutes, it's going to throw a code. You can reset it (disconnect the battery for a few minutes) and it comes back no code, but it'll come back if you don't hook that hose back up.

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