does a 93 civic dx wiring harness different from a 99 civic dx wireing harness cause i want to switch to OBD 1 and i just want to make sure or do you guys have a easier way..plus i have a OBD 1 ecu that why i asked this question

 

yes they differ........you need an obd2------>obd1 conversion harness

 

I'm going to assume that you have a 99 DX. If you want to get an OBD1 ecu for your car, then you need what djfob said, a conversion harness (OBD2B to OBD1).

 

and do a 2 wire iacv conversion.