So I got a b20 in a ek coupe and using a obd2 p75 and 96-98 ex harness. Once in a while the check engine light comes on then when i turn off the car and try to turn it back on, it wont turn on. I have to do it like a few times before it turns on. If i unplug the ecu and plug it back in, the check engine light disappear. When my cousin installed it for me he cut 2-3 wires where the ecu plugs goes, I was wondering would that be the problem? or what could it be?

 

Pull the code
find out which wires were cut and why