Ok heres the deal. My nephew has a 1991 Cvic Hatch SI and has a JDM D15B SOHC VTEC with a P08 ECU and a 0BD0 to OBD1 harness. I really dont know too much about this setup but my question was, is there a reason why the car is running rich and flashing the CEL (it blinks off and on constantly). He just bought the car and wanted me to look at it but im not sure if this is common when using the harness.

 

I know obd0 ecu has a flasher on the ecu it self. That's how u diagnose the cel versus jumping the ecu like obd1 or scanning like obd2. I thought the p08 was obd1? Hmmm, since he has a vtec motor, be sure he has vtec wires and knock sensor. As far as running rich, well it's best to see what codes the ecu is throwing to further diagnose.

 

The CEL is blinking codes. Check whether the service connector is jumped. Click the codes link in my signature.