I have a 90 pm6 ecu for my si engine.

When I short the 2P connector for timing adjustment my check engine light does not come on. The lamp in the dash does work when starting the car.

However, when I do jump the 2P connector the ecu does flash the little red LED light indicating that it is in diagnostic mode.

I am asking this question b/c my crx si is occasionally misfiring and I've been told that a bad ecu can cause this to happen.

thanks