Fuel Supply Line: Service and Repair
WM 203819 Removing and installing fuel supply line
Tools
Technical values
Preliminary work
1. Remove the engine.
-> 100119 Removing and installing 3.6-litre DFI engine 100119 Removing and installing V8 4.8-litre DFI engine.
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2. Remove right rear wheel.
-> 44051900 Removing and installing wheel Removal and Replacement.
3. Remove rear right wheel housing liner.
-> 536919 Removing and installing rear wheel housing liner Service and Repair.
4. Detach carbon canister with degassing tank and filler neck.
-> 202519 Removing and installing carbon canister on DFI engines.
-> 201019 Removing and installing fuel tank on DFI engines Service and Repair.
5. Open the filler flap.
6. Fold rear seat forward.
7. Fold up the retaining brackets for the seat-belt buckles => Fastening screws for retaining brackets for seat-belt buckles.
7.1. To do this, loosen the fastening screws and fold up the bracket with the seat-belt buckle. Fastening screws must be replaced.
Fastening screws for retaining brackets for seat-belt buckles
Removal
Removing fuel line
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.
Information
- The description applies to all engine types.
- The setup and procedures required may differ slightly from the illustrations or procedures described due to engine-specific differences.
Component overview and line routing:
Fuel line routing on the underbody
1. Remove lids for the two fuel tank flanges.
1.1. To do this, cut out the carpeted floor at the perforation using a carpet knife and fold it over.
1.2. Then unscrew the M6 fastening nuts -arrows- and remove the lids.
Fastening nuts for lids
2. Disconnect the fuel pressure line (supply) -1- at the flange.
2.1. Press the two release buttons at the same time and pull the rapid-action coupling up and off.
Fuel supply and connection points without auxiliary heating
Tank flange with connection for auxiliary heating -2-
3. Disconnect fuel lines at the connection points in the engine compartment.
3.1. Pull off plastic cover -1-.
3.2. Loosen the screw-in sleeve (wrench size 17) on the pressure line -2- and counter at the hexagon (wrench size 19) on the connecting line at the same time.
3.3. Disconnect line for tank ventilation -3-.
3.4. Pull off the line for the leakage diagnosis pump if necessary -4-.
3.5. Open the line bracket at the bulkhead.
Fuel line connection points in engine compartment
4. Remove heat shields -1-.
4.1. Unscrew three M6 collar nuts -3- and one M6 screw -1- and remove the heat shields.
Heat shields on underbody (bulkhead area)
5. Remove heat shield -1- on cardan shaft.
5.1. Unscrew two M6 screws -2- and one M8 collar nut -3- and remove the heat shield.
Heat shield on cardan shaft
6. Lower the fuel tank.
6.1. Place a transmission jack (e.g. transmission jack V.A.G 1383 A WE 1082 ) in position to support and secure the fuel tank.
6.2. Unscrew fastening screws for the restraining straps and carefully lower the fuel tank.
-> 201019 Removing and installing fuel tank on DFI engines Service and Repair.
7. Open all line brackets on the underbody and remove the wire harness.
Installation
Installing fuel line
Information
- The description applies to all engine types.
- The setup and procedures required may differ slightly from the illustrations or procedures described due to engine-specific differences.
1. Position the vehicle-specific wire harness on the tank and in the engine compartment => Fuel line routing on the underbody.
1.1. Secure the wire harness with the line brackets => Fuel line routing on the underbody.
Fuel line routing on the underbody
2. Route the line connections for the tank flange.
Line connections for tank flange
3. Fit rapid-action coupling(s) at the tank flange -1- or -1 and 2-.
Fuel supply and connection points without auxiliary heating
Tank flange with connection for auxiliary heating -2-
4. Raise the fuel tank using transmission jack V.A.G. 1383 A WE 1082.
-> 201019 Removing and installing fuel tank on DFI engines Service and Repair.
4.1. Position covers and secure restraining straps with the M8 screws.
Tighten screws to the specified torque.
=> Tightening torque: 23 Nm (17 ftlb.)
5. Fit heat shields.
5.1. Tighten three M6 collar nuts -3- and one M6 screw -2- to the specified torque.
=> Tightening torque: 10 Nm (7.5 ftlb.)
Heat shields on underbody (bulkhead area)
6. Fit heat shield -1- on cardan shaft.
6.1. Tighten two M6 screws -2- and one M8 collar nut -3- to the specified torque.
=> Tightening torque: 10 Nm (7.5 ftlb.)
=> Tightening torque: 20 Nm (15 ftlb.)
Heat shield on cardan shaft
7. Route fuel lines in the engine compartment.
Fuel line connection points in engine compartment
8. Connect fuel lines in the engine compartment.
8.1. Connect tank ventilation line -2-. Listen for a clearly audible locking noise.
Pull to check that the line is secure.
8.2. Connect connection for leakage diagnosis pump -3- if it is used.
8.3. Fit the fuel pressure line (supply) -4- as described in the next step.
Lines on plenum panel
9. Screw on fuel pressure line.
Threaded joint for fuel pressure line (supply)
9.1. Align the markings on the threaded connection -2-.
9.2. Hold the connecting line -1- for the fuel collection pipe securely and screw in counterpart component -3-.
9.3. Tighten the threaded joint to the specified torque and counter at the hexagon on the connecting line -1- at the same time using an open-ended wrench (a/f 19).
=> Tightening torque: 35 Nm (26 ftlb.)+/-10 %
10. Fit plastic cover -1-.
Fuel line connection points in engine compartment
Subsequent work
1. Fold up the retaining brackets (left and right) for the seat-belt buckles. To do this, loosen the fastening screws and fold up the bracket with the seat-belt buckle. Do not use the same fastening screws again.
2. Tighten the mounting plates for the seat-belt buckles.
2.1. Use three new fastening screws and tighten to the specified torque.
=> Tightening torque: 50 Nm (37 ftlb.)
Fastening screws for retaining brackets for seat-belt buckles
3. Fold rear seat back.
4. Secure carbon canister with degassing tank and filler neck.
-> 202519 Removing and installing carbon canister on DFI engines.
-> 201019 Removing and installing fuel tank on DFI engines Service and Repair.
5. Close the filler flap.
6. Install rear right wheel housing liner.
-> 536919 Removing and installing rear wheel housing liner Service and Repair.
7. Fit right rear wheel.
-> 44051900 Removing and installing wheel Removal and Replacement.
=> Tightening torque: 160 Nm (118 ftlb.)
8. Install the engine.
-> 100119 Removing and installing 3.6-litre DFI engine 100119 Removing and installing V8 4.8-litre DFI engine.
-> 100119 Removing and installing V8 4.8-litre DFI engine 100119 Removing and installing V8 4.8-litre DFI engine.