3.3 - Electrical Testing
Electrical Pump Voltage Testing
Voltage is critical at the pump to obtain maximum performance (pressure and volume).
A bad connection or ground will affect the pump's speed and reduce the pressure.
A problem can occur anywhere between the underhood fuse box to the fuel tank.
Do a voltage drop tests at points like: the fuel pump relay, the fuel pump connector, and the pump grounds.
Use a multimeter for exact voltage reading.
Wiring and Connectors Inspection
Some GM vehicles are affected at the pump wiring harness connector. When disconnected, we can observe overheating of the terminal portion on the fuel pump connector or on the vehicle harness connector. Make sure to install the wiring harness connector when it is supplied in the packaging.
