This is on a 90 civic ex with the d16a6 and pm6 ecu. I was driving home earlier when I got a CEL and the car went into what I assume as safe mode because it lost power as soon as that happened. Anyways I got home and turned the key half off, at least to turn off the engine but radio was still on. I put it back into position two but the ecu blinks once as it powers up(normal) but nothing after that.

I thought the error codes stayed in the ecu's memory until you reset it.

I started the car back up and no CEL but I have no idea what it was now...

Should I keep the car running next time I check the cel?

 

try disconnecting the negative battery cable to reset the ecu....

 

I know how to reset an ECU but the thing is I have no idea what the CEL was for because the ECU won't blink out any codes like it should until I reset.

 

yeah that happend to me and it was my o2 sensor.