Fuel System - Overview: Fuel
When equipped with a single fuel tank, the IPC receives the fuel level data from a single fuel level sender. The IPC sends a reference voltage to the fuel level sender. As the fuel level changes, a float actuates the variable resistor fuel level sender, converts sender voltage to Fuel Level Percent Status (FLPS) value, and sends FLPS to the PCM. PCM calculates the fuel gauge pointer position, PCM sends the fuel gauge pointer position to the IPC, and IPC displays fuel gauge pointer position.
| Item | Description |
|---|---|
| 1 | Supply flow to engine |
| 2 | Fuel Recirculation valve(oil filter/conditioner) |
| 3 | Box filter (under vacuum) |
| 4 | Water reservoir |
| 5 | Vacuum chamber |
| 6 | Fuel pump |
| 7 | Pressure damping chamber |
| 8 | Primary fuel tank |
| 9 | Auxiliary tank |
| 10 | Jet pump |
| 11 | Filler pipe and cap |
| 12 | Air bleed (jet pump feed) |
| 13 | Float valve (jet pump flow control based on fuel level and prevents fuel transfer above a predetermined fuel level) |
| 14 | Umberlla valve |
When equipped with dual fuel tanks, the IPC receives fuel level data from both primary and auxiliary fuel level senders. The fuel pump operates a jet pump in tank diesel delivery module that transfers fuel from the auxiliary fuel tank to the primary fuel tank. This functions similar to the saddle-type fuel tank design except that there are 2 separate fuel tanks that need to be refueled independent of one another. The primary fuel tank maintains a higher level of fuel due to the transfer function of the jet pump. For further information, refer to the vehicles owner manual. The IPC sends a reference voltage to the fuel level senders. As the fuel level changes, a float actuates the variable resistor fuel level senders, raising or lowering the fuel level signal voltages. The IPC monitors the changes in voltage from both senders, converts each sender voltage to two different Fuel Level Percent Status (FLPS) values, and sends the two FLPS values to the PCM. PCM calculates the main fuel gauge pointer position and individual gauge pointer positions, PCM sends the fuel gauge pointer positions to the IPC, and IPC displays fuel gauge pointer positions. . In addition to the main fuel gauge, the message center provides virtual fuel gauges for each individual tank on all Instrument Panel Clusters (IPCs).
After a fuel fill up, the time for the fuel gauge to move from empty (E) to full (F) ranges from 2 seconds to 55 minutes depending on which operating mode the fuel gauge is in.
The IPC uses 4 different operating modes to calculate the fuel level:
- Anti-slosh (default mode)
- Key OFF fueling
- Key ON fueling
- Recovery