Alright my car is a 91 CRX Dx with a B18B1 completely rebuilt long block and a OBD0 LS cable tranny. Everything was rebuilt right and time was tooken on the motor. Rings were replaced so i know how the short block is looking. The thing is that the head was given to be looked at. Afterwards, the new OEM head gasket that was put on was not replaced after the head was pulled off again, but the head was on for only a while and the car was checked out to see if it was gonna fire up ghood and everything was done right and it was. But then the thoughts of having someone port and polish it played in mind and thats when it was pulled again. To make a long story short, the head never got port n polished and it was laid back down on the same head gasket. The motor is completely well except the fact that cylinder #4 is misfiring - sounding like the #4 spark plug wire was pulled, but it's not. I want to know can this #4 cylinder become alright if i was to just replace the head gasket? Because it has low compression after the compression test was performed and the rest are at normal compression readings. Real answers are appreciated, thanks.