Fuel Pump Module
| ITEM | DESCRIPTION |
|---|---|
| 1 | Fuel return connection |
| 2 | Fuel supply connection |
| 3 | Fuel level sensor electrical connector |
| 4 | Fuel pump electrical connector |
| 5 | Fuel Fired Booster Heater (FFBH) fuel supply connection - If equipped |
| 6 | Fuel inlet filter |
| 7 | Fuel Fired Booster Heater (FFBH) suction tube and seal - If equipped |
| 8 | Fuel level sensor float |
| 9 | Swirl pot |
| 10 | Active fuel level sensor |
| 11 | Jet pump connection - Left (passive) side of fuel tank |
| 12 | Flange locking ring and O-ring seal |
The Low Pressure (LP) fuel pump module is controlled by the Powertrain Control Module (PCM) via the fuel pump relay. The fuel pump relay is located in the Rear Junction Box (RJB).
The LP fuel pump module is located in the right side of the tank. The LP fuel pump module flange is sealed to the tank with an O-ring seal and secured with a locking ring.
The top flange of the LP fuel pump module assembly provides the internal and external interface for the tank electrical and fuel connections. The top flange comprises a connection for the internal and external fuel tank breather pipes as well. The flange has external electrical connectors that are connected to the active and passive fuel level sensors, and the LP fuel pump.
The lower part of the LP fuel pump module forms the fuel swirl pot, and provides the location for the LP fuel pump. The swirl pot provides a constant reservoir of fuel for the engine drawn fuel supply.
The fuel is transferred using a venturi pump. The venturi effect is the reduction in fluid pressure that results when a fluid flows through a constricted section of a pipe. The venturi effect is created by the fuel feed flow from the fuel pump. The rapid flow of fuel through the suction pipe creates a depression. The depression draws the fuel back from the left (passive) side of the fuel tank into the fuel pump (active) side of the fuel tank.
The second venturi effect draws the fuel from the pump side of the fuel tank into the swirl pot. Surplus fuel entering the fuel swirl pot overflows into the usable right side of the fuel tank. The LP fuel pump provides sufficient fuel in the swirl pot to feed the High Pressure (HP) fuel pump.
Depending on vehicle configuration, vehicles can be equipped with a Fuel Fired Booster Heater (FFBH). The LP fuel pump module has a separate pipe connection for the fuel supply line that is connected to the FFBH fuel pump. The FFBH fuel pump is mounted on the exterior right side of the fuel tank. This pipe connection is equipped with a sealed suction tube which draws fuel from the swirl pot. An additional fuel line connects the FFBH fuel pump to the FFBH fuel inlet. For additional information, refer to: FUEL FIRED BOOSTER HEATER .