Leave key on and wait about 30 seconds, fuel pump runs again for 2 seconds and cel goes out. Will now start. New main relay, new coil, new rotor cap. Bypassed ignition switch and same. Check 5 vlts reference at map sensor when cel on and 5 vlts present. Ran car with map sensor unplugged, and computer picked up on it so computer seems OK. Have pin out for computer, checked voltage where should be all good except on A-21 ignition control module output signal should have about 10vlts according to pinout, but test light shows no voltage

Thoughts:

. Check all under hood and under dash fuses with a test light or multimeter.

. Check the ignition switch for wear, pitting, or melting.

. Clean the main ECM ground, located on the thermostat housing.

. See if the CEL staying on is related to the Throttle Position Sensor (TPS). If so, replace the TPS.

All fuses good. I bypassed the switch and the problem is still there. I cannot find any ground attached to or near thermostat housing, however all grounds checked out at the ecu connectors. The ECU pin A21 does not have pos vltage as pinout says??

ECU pin A-21 is listed as ignition control module output and should have pos voltage, but does not? Is that a clue to problem

I suspect the ECM is failing, in a more subtle way, even though it passes the K-Test. It's common on these older Hondas.