After swapping the engine I was driving the car and after being driven for an hour or so the oil light comes on even though it was full. Checked the oil and not a single drop was lost. Tried driving it again and then it was off at first then came on, then erratically flashed and not in a pattern when oil pressure is bad but just random. Now I don't have the car here, left it at my pop's shop for them to look over but it'll be whenever they get a chance so I'm trying to see if anyone knows what the best thing would be to look for so that I can get this thing back in action. Using H23a1 harness btw and this was not happening before the swap so I don't think its the wiring, thanks for any input.

 

check to make sure that the wire that screws to the factory oil pressure sending unit is tight and not making a bad connection, cause if it looses connection the light will go on and off for no reason.
you need to hook a oil pressure gauge up to the motor and check physical pressure though. h22's are known for oil pump failures. better safe then sorry.