96 Z, is there any way to check the engine wiring harness for shorts, no codes, tune got gone crazy, same tune that I have been running for two months now, all trims are out of balance, it changes each time I run the car, have not changed any thing, but each time I start it up it's different from the last run. I really think it's in the wiring some where and seems there should be away of checking the harness for possible bad wires. any ideas how.

 

You can check voltage and ground potentials as well as resistance (circuit must be open) with a multimeter.