just got finished replacing fuel pump with a new aftermarket one and now everything works but when i put the van in reverse the gauge drops to empty but if i put it in any other postion everything works fine. when i did the key on/off trick i got #42. while i have power to the pump i have 3.5 volts on the blue wire in every gear except reverse when i put it reverse the voltage shoots up to 11 volts and the gauge drops to empty. Any ideas would be greatly appreciated

it turned out to be in the wiring of the new fuel pump