I have a problem with my 89 crx hf.....to start off I did the d16a6 swap and now have the check engine light for o2 sensor. I bought a new one, cleared the ecu and it comes on again after warm up. I tried a different si ecu and same thing. one issue, the guy who did the swap for me used the hf harness. I also put ina new thermostat and cooloant temp sensor I dont know what else to do. for some reason Im thinking it runs rich or lean because it eats up a lot of fuel.... please help!!!

 

did you disconnect the (-) on youe battery for like 20sec to reset the ecu to clear all the codes?

 

yeah, but afeter the motor warms up it comes on again and it starts runing pretty shitty but not too much that I cant drive it.

 

check the connector to the O2 sensor. Grab the wires and push them into the connector.

Also if that doesn't do it make sure the ECU is seeing the O2 voltage by backprobing the ECU connector. It should read less than 1volt.