Our power washer stopped getting power and it appeared that the GFCI plug at the end of the cord was defective. I bought a new GFCI plug and proceeded to swap out the old one. The instructions that came with it said I needed a 3 wire cord. The cord on the power washer is only a 2 wire cord with no ground wire. If I just leave the ground spot empty how will this affect the way it is supposed to work?