Check Engine light turning off when E30 is warmed-up

[edricklamar]

Check Engine light turning off when E30 is warmed-up


This question has been probably asked many times already, and after searching for a while, I still can not find an answer.

This is for a 1988 E30 325 Coupe ETA model. Background: When I first turn on the ignition, without cranking the engine, the CEL flashes 2x: Motronics 1.x (Emissions (lambda) Controls) or Oxygen sensor. After driving for a while, warming-up the engine, turning off the car, and playing with the ignition switch(without cranking the engine) the check engine light turns off (returns to a normal operating condition, and the CEL code returns to normal or no fault), and stays off as long as the air intake is cool, but if it is as hot day, the CEL will turn back on after driving a short interval, and I would have to repeat the steps mentioned to clear CEL. I am tending to replace the O2 relay since it is inexpensive, and it probably needs one anyways.

The vehicle did pass California Test-Only smog check, so I am good for another 2 years, and the car runs smooth.

Has anyone experienced this before?