I recently bought a Honda Integra zc with a b18c2 engine swapped by the previous owner. And I am having few troubles with my engine. Having miss fires knocking. Can It be because of my ecu not being P72? Because the previous owner said he put the P72 in his previous ecu box my integra. I am not sure if it's a P72 because there's no code of P72 In it because of it having previous engine ecu code. How will I know if it's a P72 obd1 or 2. Also can any other ecu work with b18c2 engine? If it does what kind of problem will I face? Sorry for long texts.

 

Unless the ECU that you have is chipped or tunable, no other ECU except a P72 will run your engine correctly. Remove the lid from your ECU and take a picture of the internals... then post it here.