Fuel Gauge Sender: Service and Repair

Removing And Installing Fuel Level Sensor

Tools







Information

Component information

NOTE:
- The two senders have different shapes and may not be switched.
- The float installed in the left direction of travel is flat, while the float installed in the right direction of travel is spherical.
- The removal of both senders is explained in parallel in this description. If only one sender has to be removed, the other side of the tank can remain untouched.







Jammed fuel-level sensor
The effect of fuel and various tolerances means that the left fuel level sensor can become jammed under fuel lines or the sensor's electric cable. The instrument cluster would then display an incorrect fuel level.

To prevent this, the two fuel lines coming from the left pump and the electric cable should be tied together with a tie-wrap following repairs.







Preliminary work

Opening the tank

NOTE: If the tank must be opened for emptying, disconnect all connections.







1. Open filler flap.
2. Fold rear seat forwards.
3. Fold up the retaining brackets of the (right and left) seat-belt buckles. To do so, loosen the four fastening screws and fold up the bracket with the seat-belt buckle. Do not use the fastening screws again.







4. Undo the caps (figure shows both). To do so, cut out the carpeted floor along the perforated lines using a carpet knife and fold it over. Then unscrew the four fastening nuts and remove the lid.







5. Empty the fuel tank if this has not already been done or if the fuel level in the fuel tank is very low.

DANGER:
Danger of poisoning from fuels.
- Gasoline is toxic.
- Inhaling vapours can cause irritation of the mucous membranes and eyes.
- It can be carcinogenic. It represents a serious risk to health when inhaled, touched or swallowed over longer periods.
- Only work on the fuel system in well-ventilated rooms.
- Wear protective gloves that are fuel-resistant.
- Wear a breathing mask with active charcoal filter; do not breathe in any fuel vapours.
- Ensure that there is adequate ventilation and extract all fuel vapours.
- Before opening the fuel lines or fuel hoses, relieve the fuel pressure.
- Collect escaping fuel, absorb it if necessary with a suitable binding material and dispose of properly.
- Pay attention to cleanliness when working on the fuel system.

DANGER:
Danger of fire from fuel.
- Keep clear of ignition sources.
- Do not smoke.
- Disconnect battery.
- Danger of fire due to naked flames and sparks, e.g. during welding or grinding work.
- Danger of fire due to escaping fuel, e.g. on hot engine components or due to electrostatic charge. Allow engine to cool down.
- Secure the vehicle, e.g. with a warning sign.
- Change any clothing soaked with fuel immediately.
- In case of fire, use CO2 or dry powder fire extinguishers.

NOTE:
- The ignition must be switched off when working on the fuel system.
- Absorb any escaping fuel using a suitable binding material or a cloth.
- Cloths which have absorbed fuel must be disposed of according to the applicable national laws.
- The fuel system must be depressurised before starting work on it.
- Only work on the fuel system in well-ventilated rooms.
- Any seals which have been removed must always be replaced.

6. Carefully remove the fuel supply -1- at the relevant connection unit (right connection unit here) and loosen the two disconnection points -2 and 3-. Also remove line (not shown here) in vehicles with auxiliary heating (auxiliary heater). Do the same at the left connection unit. Disconnect all connections on the connection unit.
7. Open the relevant cap with the key T10202 and lift up the connection unit (cap).







Preliminary work
1. Disconnect electric connectors -1 and 2-. Then pull off the fuel lines -3 and 4- and remove the connection unit.







Removing fuel level sensor
1. Reach carefully past the fuel pump and feel for the sender. This is located in front of the pump, pointing diagonally outwards.
2. Press the retaining spring on the sender by hand while at the same time pulling the sender up.







Installing fuel level sensor
1. Install a new tank gauge. Press the sender into its mounting. The retaining spring must engage audibly.












Subsequent work
1. Fit new seal in the opening of the tank.







2. Connect connection unit. Connect the electric connectors for the tank gauge and fuel pump. Then push on the fuel lines. The connectors must engage audibly.







3. Fit connection unit into tank opening. When doing so, make sure that the plastic lug is pointing forwards.

Closing the tank
1. Close the tank. To do so, fit the sheetmetal ring and tighten using the key T10202. Tightening torque: 104 ftlb.







2. Fit all connections (fuel lines, ventilation tubes and electric plugs).







3. Fit the lid. Then tighten the four fastening nuts. Tightening torque: 7.5 ftlb. Refit carpeted floor and fix with double-sided adhesive tape.







4. Tighten the seat-belt buckle fastening plates. Use three new fastening screws for this and tighten.







5. Fold rear seat down again.
6. Fill fuel tank (refuel).