Noticed here lately sometimes I turn the key on to start the truck and there's no buzzing from the fuel pump- gauge stays on zero. If I turn the motor over it spins but no run. If I turn the key off and back on the pump buzzes and the truck starts right up. Is this possably the ignition switch? A relay somewhere? Something more serious? I have the aftermarket pump setup (the good one) mounted to the frame and the one on the engine bypassed. This is a 98.5 24 valve Cummins. Any ideas? Thanks-