Me and my buds were installing a new F.A.S.S. fuel pump from PDR Diesel Performance on his 2005 Cummins Standard. After we followed the instructions for installment we started up the truck. The engine just doesn't sound right like it was knocking harder when it would combust. Then we took it for a test drive and he just had no power what so ever, he can't even get it above 3,000 RPM when the pedal is on the floor. The fuel pump also heats up after it runs for a while, but then the weird part is that even without the harness connected, the truck still ran, with the harness connected we couldn't hear the fuel pump running like others say it does with a hum. So we reconnected his factory fuel pump system back up and the problem still continued. So what went wrong? Any help would be very much appreciated.