- Remove the fuel pump, and then remove the fuel level sensor attached to the pump assembly.
- Temporarily reconnect the electrical connectors for the fuel level sensor.
- Turn the ignition switch to the ON position, but Do NOT attempt to start the engine.
- Move the sensor float up and down while observing the fuel level gauge. The gauge should move as the float is moved.
The actual float resistance can be checked using an ohmmeter.
Sensor resistance is as follows, based on fuel level in tank:
rEMOVAL & INSTALLATION
The fuel sender is located in the fuel tank. A large plastic lock ring must be loosened and removed on all models, before sender is removed. It may be necessary to remove the lock ring using Tool No. 3217.
On Audi A4 models and 1998-00 Passat models the fuel sender is attached to the fuel pump which secured into a mounting bracket the fuel tank. The fuel pump must be rotated approximately 15° counterclockwise to remove. It may be necessary to remove the fuel pump on these models using Tool No. 3307.
- The sending unit is accessed by removing bottom trunk trim cover, then removing the access panel. On models with folding down rear seats, the rear seats can be folded down to allow additional access.
- Disconnect the wiring.
- Label and disconnect the fuel lines.
- Unscrew the locking ring turning it counterclockwise using Tool No. 3217 if necessary.
- On 1990-97 Passat models, lift the sending unit and transfer pump straight out.
- On A4 and 1998-00 Passat models, turn the fuel pump assembly 15° counterclockwise to release the fuel pump. If necessary use Tool No. 3307 to release, and upon assembly, to install the fuel pump.
- Before installing the unit, check the condition of the O-ring and if OK, coat lightly with fuel, otherwise replace it if necessary.
- Installation is in reverse order of removal.