I recently just swapped a b18C into a 99 civic hatch. I used a rywire obd2 to obd1 harness and it plugs into a stock p28. I can crank the car but it doesn't start, initially I thought it was my fuel pump but it worked with my last engine. So why doesn't it start.

 

Do you have a RyWire ECU conversion harness or a RyWire engine harness ? If it is an ECU conversion harness, is the engine harness plugged into the conversion harness the same way as it was plugged into the original EM1 ECU ?