Fuel Supply System Audi S8 D3 рестайлинг

Contact corrosion!

1. Contact corrosion can occur if appropriate connecting elements (bolts, nuts, washers, etc.) are not used.
2. For this reason, only install connecting elements that are treated with a special coating.
3. Furthermore, all rubber, plastic parts and adhesives are made of non-conductive material.
4. If you have doubts about the reusability of parts, generally install new parts.

Safety precautions

The following steps should be taken before beginning work on fuel supply system

1. Disconnect Ground (GND) wire at battery Ground (GND) terminal with ignition switched off.
2. Open fuel filler flap briefly and then close again.

When removing and installing components from full or partially full fuel tanks, the following must be observed

1. The fuel tank may only be partially full. How much fuel can remain in the fuel tank may be read in the respective work description. Empty fuel tank if necessary --> «Fuel tank, emptying»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__fuel-tank-emptying) .
2. Before starting work, switch on exhaust extraction system and place an extraction hose close to the installation opening of fuel tank to extract escaping fuel fumes. If no exhaust extraction system is available, a radial fan (as long as motor is not in air flow) with a displacement greater than 15 m 3 /h can be used.
3. Prevent fuel from contacting skin! Wear fuel-resistant gloves!

Note the following when removing and installing fuel tank

1. Fuel tank must be empty for weight reasons. Empty fuel tank if necessary --> «Fuel tank, emptying»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__fuel-tank-emptying) .

Rules for cleanliness

When working on the fuel supply/injection system, pay careful attention to the following rules of cleanliness

1. Thoroughly clean all connections and surrounding area before disconnecting.
2. Place parts that have been removed on a clean surface and cover them. Do not use fluffy cloths!
3. Carefully cover over opened components or seal, if repairs are not performed immediately.
4. Only install clean components: Only unpack replacement parts immediately prior to installation. Do not use parts that have been stored unpackaged (e.g. in tool boxes etc.).

1. When system is open: Do not work with compressed air. Do not move vehicle unless absolutely necessary.

Scheme 1

1 - Securing strap

1. With spacer, installed location «Installed location of spacer»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system)

2 - 22 Nm

3 - Fuel line

1. From fuel filter
2. To engine
3. To disconnect, press release button on connection piece

4 - Fuel return line

1. From engine
2. To disconnect, press release button on connection piece
3. Clipped in on fuel tank

5 - Vent line

6 - Ground (GND) connection

1. For discharging electrostatic charge
2. Installed position/check requirements --> «Installation position of Ground (GND) connection»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system)
3. Make sure connector is securely seated.
4. After installing, check electrical connection of fuel filler tube to a bare area of chassis using Ohm meter - Specified value: approx. 0ohms

7 - Cap

1. With Fuel Tank Lock Switch F314 solenoid --> «Locking cover with solenoid»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system)

8 - Seal

1. Replace if damaged

9 - 22 Nm

10 - Electrical harness connector

1. For Fuel Tank Lock Switch F314 --> «Fuel Tank Lock Switch F314»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system)

11 - Vent line

1. To evaporative emissions (EVAP) canister in spare wheel well on vehicle floor
2. Remains on fuel tank when fuel tank is removed

12 - Fuel tank

1. Removing and installing --> «Fuel tank with attachments, removing and installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__fuel-tank-with-attachments-removing-and)

13 - Bushing

14 - Fuel tank bracket

15 - 22 Nm

16 - Rubber buffer

17 - Washer

18 - 22 Nm

19 - 22 Nm

20 - Securing strap

1. With spacer, installed location --> «Installed location of spacer»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system)

21 - Retaining clip

1. For heat shield

22 - Heat shield

23 - Retaining clip

1. For heat shield

Scheme 2

1. Make sure that the spacer of securing straps is seated directly below seam of fuel tank - arrow -.

Scheme 3

1. Route Ground (GND) connection (Scheme 3)
2. Ensure connector of Ground (GND) connection fits securely at metal ring of fuel filler tube - arrow -.

Scheme 4

1. Ensure electrical connector - 2 - for Fuel Tank Lock Switch F314 - 1 - is seated properly on fuel filler neck.

Scheme 5

1. Fuel Tank Lock Switch F314 solenoid - arrow -.

Fuel tank, emptying

Special tools, testers and auxiliary items required

Scheme 6

1. Fuel siphoning unit VAS 5190

Scheme 7

1. Vehicles from approx. 11/2002: Wrench T10202

Work procedure

Observe safety precautions --> Safety precautions .

Observe rules for cleanliness --> Rules for cleanliness .

1. Open fuel filler flap briefly and then close again.

1. Remove cover of right luggage compartment side trim - arrows -.

Scheme 8

1. Remove cover - 1 - above battery.

Note. Ignore - 2 -.

Scheme 9

1. With ignition switched off, disconnect Battery Ground (GND) strap - arrow -.

Scheme 10

1. Remove trim for luggage compartment floor.
2. Remove cover for left locking flange - arrows -.

Scheme 11

1. Disconnect electrical connectors - 1 - and - 2 - at left locking flange.

Scheme 12

1. Remove locking ring using wrench T10202.

Scheme 13

1. Remove cover for right locking flange - arrows -.

Scheme 14

1. Disconnect electrical connectors - 1 - and - 2 - at right locking flange.

Scheme 15

1. Mark fuel return line - 1 - and fuel supply line - 2 -.

1. Pull both lines from locking flange, by pressing release buttons.

1. Remove locking ring using wrench T10202.

Scheme 16

1. Connect Ground (GND) wire of Fuel Extraction Unit VAS 5190 to ground terminal of energy management control module J644.
2. Pull off left locking flange and set aside with electrical wiring still connected.
3. Remove seal.
4. Extract fuel in left half of fuel tank through opening in fuel tank, using fuel extraction unit VAS 5190.

Scheme 17

1. Pull off right locking flange and set aside with electrical wiring and fuel lines still connected.
2. Remove seal.
3. Extract fuel in right half of fuel tank through opening in fuel tank, using fuel extraction unit VAS 5190.
4. Re-install locking flange: Left --> «Installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__installing) , Right --> «Installed location of right locking flange»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__installed-location-of-right-locking-flange) .

Fuel tank with attachments, removing and installing

Special tools, testers and auxiliary items required

Scheme 18

1. Engine/transmission jack V.A.G 1383 A

Scheme 19

1. Support T10031

Removing

Observe safety precautions --> Safety precautions .

Observe rules for cleanliness --> Rules for cleanliness .

1. Release fuel tank flap.

1. Remove cover of right luggage compartment side trim - arrows -.

1. Remove cover - 1 - above battery.

Note. Ignore - 2 -.

1. With ignition switched off, disconnect Battery Ground (GND) strap - arrow -.

1. Remove trim for luggage compartment floor.
2. Remove for right locking flange - arrows -.

Scheme 20

1. Disconnect vent line - arrow - by pressing releases.

1. Remove rear axle --> «42 - REAR SUSPENSION»(/audi/s8/d3-2007-2011/remont/axle-shafts/#suspension-wheels-and-steering) .
2. Remove right rear wheel housing liner --> «66 - EXTERIOR EQUIPMENT»(/audi/s8/d3-2007-2011/remont/door-locks-anti-theft-systems/#body-exterior) .

Scheme 21

1. Disconnect Ground (GND) wire - 3 - from fuel filler tube.
2. Disconnect electrical connector - 1 - for Fuel Tank Lock Switch F314.
3. Disconnect vent line - 5 - from fuel filler tube.
4. Remove bolts - 2 - and - 4 - for fuel filler tube.

1. Make sure driveshaft is secured from falling down.

1. The driveshaft must be set on a wooden block - 1 - and be secured with wire or cable - arrow -.
2. Make sure that the driveshaft is angled slightly downward so that the fuel tank can later be guided over this and out during removal.

Note. The max. allowable angle of the driveshaft must not exceed 8°.

Scheme 22

1. Remove heat shield for driveshaft - arrows -.

Note. The heat shield is also clipped in at the top to the vent line.

Scheme 23

1. Remove left cover - 1 - from bottom of vehicle floor.

Scheme 24

1. Remove right cover - 1 - from bottom of vehicle floor.

Scheme 25

1. Disconnect electrical harness connectors

2 - To fuel pumps

3 - To fuel gauge sensors

1. Separate fuel lines by pressing release buttons

1 - Fuel return line

4 - Fuel supply line

Scheme 26

1. Disconnect right rear vent line - arrow - on fuel tank by pressing release button.

Scheme 27

1. The brake calipers, that were previously hung on fuel tank brackets when rear axle was removed, must now be attached to struts with wire - arrow -.

Scheme 28

1. Place Engine/transmission jack V.A.G 1383 A with support T10031 (without threaded rods) under fuel tank for support.
2. Support fuel tank using engine/transmission jack V.A.G 1383 A and support T10031.
3. A second technician must also support fuel tank by hand at rear edge.

Scheme 29

1. Remove bolts - 1 to 6 - and if necessary, pivot fuel tank brackets forward.
2. Lower fuel tank toward rear slightly so that the fuel filler tube can be guided out of body.
3. Lower fuel tank using Engine/transmission jack V.A.G 1383 A , guiding it by hand.

Note. To improve clarity, the fuel tank is shown without Engine/transmission jack.

Installing

1. Tightening torques --> «Fuel tank with attachments, assembly overview»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system) .

Scheme 30

1. Check whether fuel lines and wiring harness to fuel pumps and fuel level sensors are clipped on brackets - 1 - on fuel tank.
2. When installing a new fuel tank, paste backing pieces - 2 - onto fuel tank, as shown in the illustration.
3. Position fuel tank with mounting straps and brackets to vehicle floor using engine/transmission jack V.A.G 1383 A and support T10031.
4. Make sure fuel tank is positioned so that the filler tube can be correctly guided into opening of body.

1. Fasten fuel tank to fastening points - 1 - , - 2 - , - 5 - , - 6 - first, and then to - 3 - and - 4 -.

1. Make sure that the spacer of securing straps is seated directly below seam of fuel tank - arrow -.

1. Fasten fuel filler tube using bolts - 2 - and - 4 -.
2. Push vent line - 5 - on until it engages audibly.
3. Connect electrical connector - 1 - for Fuel Tank Lock Switch F314.
4. Check if Ground (GND) wiring - 3 - and contact show signs of oxidation. If necessary, remove.

The rest of installation is in reverse order of removal, note the following

Note. Replace seals and gaskets when performing repair work. Secure all hose connections using hose clamps appropriate for the model type .

1. Install rear axle --> «42 - REAR SUSPENSION»(/audi/s8/d3-2007-2011/remont/axle-shafts/#suspension-wheels-and-steering) .
2. Install right rear wheel housing liner --> «66 - EXTERIOR EQUIPMENT»(/audi/s8/d3-2007-2011/remont/door-locks-anti-theft-systems/#body-exterior) .
3. Install rear part of exhaust system --> «26 - EXHAUST SYSTEM, EMISSION CONTROLS»(ref-289203-S15160552682008062700000) for 4.2 LITER V8 4V ENGINE MECHANICAL, ENGINE CODE(S): BVJ 26 - EXHAUST SYSTEM, EMISSION CONTROLS for 4.2 LITER V8 5V ENGINE MECHANICAL, ENGINE CODE(S): BFM, BGK «26 - EXHAUST SYSTEM, EMISSION CONTROLS»(/audi/s8/d3-2007-2011/remont/cooling-fan/#52l-10-cyl-4v-engine-mechanical-engine-codes-bsm) for 5.2 LITER 10-CYL. 4V ENGINE MECHANICAL, ENGINE CODE(S): BSM «26 - EXHAUST SYSTEM, EMISSION CONTROLS»(ref-289206-S39019950152008062700000) for 6.0 LITER 12-CYL. 4V ENGINE MECHANICAL, ENGINE CODE(S): BHT, BSB .
4. Connect battery. Observe safety precautions after connecting battery --> «27 - BATTERY, STARTER, GENERATOR, CRUISE CONTROL»(/audi/s8/d3-2007-2011/remont/cruise-control-systems/#electrical-equipment) .

In-tank wire routing, assembly overview

Note. The illustration shows the ideal routing of the lines on the inside of the fuel tank. With exception of the line position --> Installed location of fuel delivery lines , exact routing of the lines is not required, although you must be generally aware of clearance between components and of preventing rattling noises. - Arrow - points in direction of travel.

Scheme 31

1 - Left fuel delivery unit with Transfer Fuel Pump (FP) G6

2 - Fuel delivery line

1. From left suction jet pump to right fuel delivery unit

3 - Suction jet pipe

1. From right fuel pump to left suction jet pump

4 - Left suction jet pump

5 - Expansion tank

1. With suction jet pump to pump fuel from reservoir

6 - Check valve

1. For fuel filler line

7 - First-time filling fuel line

1. To right fuel delivery unit
2. Serves to supply a small amount of fuel directly to delivery unit during first-time filling

8 - Right suction jet pump

9 - Suction jet pipe

1. From right fuel pump to right suction jet pump

10 - Fuel delivery line

1. From right suction jet pump to left fuel delivery unit

11 - Right fuel delivery unit with Fuel Pump (FP) G23

12 - Vent line

1. To vent connection at top on fuel filler neck

13 - Fuel supply line

1. From left and right fuel pumps to locking flange

14 - Vent line

1. To evaporative emissions (EVAP) canister in spare wheel well on vehicle floor

15 - Fuel filling line

1. From filler tube to check valve in fuel tank

16 - Fuel return line

1. From locking flange to left and right fuel delivery units

17 - Suction jet pipe

1. To suction jet pump in reservoir

Scheme 32

1. The delivery lines - 1 - and - 3 - must be routed under \ fuel filler line - 2 - in \ area of \ left fuel tank opening.

Scheme 33

1 - Support

1. For fuel delivery unit

2 - Fuel Level Sensor G

1. Black
2. Clipped into mount - 1
3. Resistance values, checking --> «Fuel Level Sensor G , checking (left lever-type sensor)»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__fuel-level-sensor-g-checking)
4. Removing and installing --> «Fuel Level Sensor G (left lever-type sensor), removing and installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__fuel-level-sensor-g-left-lever-type)

3 - Left fuel delivery unit

1. With Transfer Fuel Pump (FP) G6
2. Clipped into mount - 1
3. Different versions
4. Fuel pump electrical, checking --> «Transfer Fuel Pump (FP) G6 (left), checking electrical»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system)

1. Checking residual pressure --> «24 - MULTIPORT FUEL INJECTION (MFI)»(ref-289205-S08445194072008062700000) for 4.2 LITER V8 4V FUEL INJECTION AND IGNITION, ENGINE CODE(S): BVJ 24 MULTIPORT FUEL INJECTION (MFI) for 4.2 LITER V8 5V FUEL INJECTION & IGNITION, ENGINE CODE(S): BFM «24 - MULTIPORT FUEL INJECTION (MFI)»(/audi/s8/d3-2007-2011/remont/cooling-fan/#52l-10-cyl-4v-fuel-injection-ignition-engine-codes-bsm) for 5.2 LITER 10-CYL. 4V FUEL INJECTION IGNITION, ENGINE CODE(S): BSM «24 FUEL INJECTION SYSTEM»(ref-289212-S05463344962008062700000) for 6.0 LITER 12-CYL. 4V FUEL INJECTION AND IGNITION, ENGINE CODE(S): BSB
2. Removing and installing --> «Left fuel delivery unit with Transfer Fuel Pump (FP) G6 , removing and installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__left-fuel-delivery-unit-with-transfer)
3. After installing, fuel vehicle with at least 5 liters of fuel

4 - Fuel delivery line

1. From suction jet pump, right side
2. Clipped onto fuel delivery unit - 3

5 - Fuel supply line

1. The connection is located on right side of fuel tank
2. To disconnect, press release button on connection piece

6 - Fuel return line

1. The connection is located on right side of fuel tank
2. To disconnect, press release button on connection piece

7 - Locking ring

1. Use wrench T10202 for removal and installation
2. Tighten to 120 Nm

8 - Left locking flange

1. Installed location --> «Installed location of left locking flange»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system)

9 - Seal

1. Replace
2. Install dry

10 - Fuel Level Sensor 3 G237

1. Gray
2. Clipped onto fuel delivery unit - 3
3. Resistance values, checking --> «Fuel Level Sensor 3 G237 , checking (left tubular sensor)»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__fuel-level-sensor-3-g237)
4. Removing and installing --> «Fuel Level Sensor 3 G237 (left tubular sensor), removing and installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__fuel-level-sensor-3-g237-left)

Scheme 34

1. Install new locking flange seal dry.
2. Insert locking flange in fuel tank, note installation position

1. Tab - 2 - on locking flange must lie between tabs - 1 - and - 3 - on fuel tank.

Scheme 35

Special tools, testers and auxiliary items required

1. Remote control V.A.G 1348/3A with adapter cable V.A.G 1348/3-2
2. Portable multimeter V.A.G 1526C
3. Connector test set V.A.G 1594C
4. Vehicle Diagnosis, Testing and Information System VAS 5051 with inductive pickup (50 A) VAS 5051/9

Work procedure

Vehicles of model year 2003

Scheme 36

1. Fuse 10 on fuse panel SF10 (in relay and fuse panel in right of luggage compartment) O.K.

Vehicles as of model year 2004

Scheme 37

1. Fuse 2 on fuse panel SF2 (in relay and fuse panel in right of luggage compartment) O.K.

All

1. Fuel Pump (FP) 2 Relay J49 O.K. (on relay and fuse panel in right of luggage compartment, Socket 3).
2. Battery voltage min. 12.5 V
3. Fuel filter OK.
4. Ignition switched off.

Checking voltage supply

1. Remove cover of right luggage compartment side trim - arrows -.

Vehicles of model year 2003

1. Pull out fuse 10 on fuse panel SF10 (in relay and fuse panel in right of luggage compartment, Socket 10).

Vehicles as of model year 2004

1. Pull out fuse 2 on fuse panel SF2 (in relay and fuse panel in right of luggage compartment, Socket 2).

Scheme 38

All

1. Connect Remote Control V.A.G 1348/3A with Adapter Cable V.A.G 1348/3-2 to right socket terminal of removed fuse.
2. Connect alligator clip on Remote Control V.A.G 1348/3A to battery "+".
3. Press switch on remote control.

1. Operating noise of pump must be audible in vicinity of fuel tank.

Note. Fuel Pump (FP) runs quietly. Avoid surrounding noises while testing the fuel pump. If necessary, use a second technician to check.

If no operating noise can be heard

1. Remove trim for luggage compartment floor.
2. Remove cover for left locking flange - arrows -.

Scheme 39

1. Disconnect electrical harness connector - 2 - at left locking flange.

Note. Ignore - 1 -.

Scheme 40

1. Connect multimeter between terminal - 1 - and - 4 - of electrical harness connector for voltage measurement.
2. Press switch on remote control.

1. Specified value: approx. battery voltage.

If specification is not obtained

1. Repair wire connection according to wiring diagram.

Scheme 41

If specified value is obtained, although no running-noise can be heard at pump

1. Remove left fuel delivery unit --> «Left fuel delivery unit with Transfer Fuel Pump (FP) G6 , removing and installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__left-fuel-delivery-unit-with-transfer) .
2. Check if electrical wiring between flange and fuel pump is connected and has continuity.

If no fault is detected in wiring

1. Fuel pump faulty. Replace left fuel delivery unit.
2. Install left fuel delivery unit --> «Installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__installing) .

Checking current draw

1. Voltage supply of Fuel Pump (FP) OK --> «Checking voltage supply»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__checking-voltage-supply) .

Scheme 42

1. Remove cover of right luggage compartment side trim - arrows -.

Vehicles of model year 2003

1. Pull out fuse 10 on fuse panel SF10 (in relay and fuse panel in right of luggage compartment, Socket 10).

Vehicles as of model year 2004

1. Pull out fuse 2 on fuse panel SF2 (in relay and fuse panel in right of luggage compartment, Socket 2).

All

1. Connect Remote Control V.A.G 1348/3A with Adapter Cable V.A.G 1348/3-2 to right socket terminal of removed fuse.
2. Connect alligator clip on Remote Control V.A.G 1348/3A to battery "+".
3. Connect Vehicle Diagnosis, Testing and Information System VAS 5051 with inductive pickup VAS 5051/9 to wire of remote control.
4. Press switch on remote control.

1. Measure current draw of fuel pump.

1. Specified value: approx. 8 A

If specification is not obtained

Note. At a displayed current draw of 4 A, Fuel Pump (FP) runs dry.

Left fuel delivery unit with Transfer Fuel Pump (FP) G6 , removing and installing

Special tools, testers and auxiliary items required

1. Vehicles from approx. 11/2002: Wrench T10202

Removing

Observe safety precautions --> Safety precautions .

Observe rules for cleanliness --> Rules for cleanliness .

1. Remove cover of right luggage compartment side trim - arrows -.

1. Remove cover - 1 - above battery.

Note. Ignore - 2 -.

1. With ignition switched off, disconnect Battery Ground (GND) strap - arrow -.

1. Remove trim for luggage compartment floor.

Note. To remove and install fuel delivery unit, remove vehicle tool kit and spare wheel from luggage compartment. It is then possible to sit or kneel in spare wheel well.

1. Remove cover for left locking flange - arrows -.

1. Disconnect electrical connectors - 1 - and - 2 - at left locking flange.

1. Remove locking ring using wrench T10202.

Scheme 43

1. Pull off locking flange and remove seal.
2. Disconnect electrical connectors - 1 to 3 - on underside of left locking flange.

1. Remove cover for right locking flange - arrows -.

1. Disconnect electrical connectors - 1 - and - 2 - at right locking flange.

1. Mark fuel return line - 1 - and fuel supply line - 2 -.

1. Pull both lines from locking flange, by pressing release buttons.

1. Remove locking ring using wrench T10202.

Scheme 44

1. Pull off locking flange and remove seal.
2. Disconnect electrical connectors - 1 to 3 - on underside of right locking flange.

Note. To separate the line couplings that are mentioned later in the description, pull the fuel lines out of the fuel tank opening. To improve clarity, the following illustration shows several components not installed.

Scheme 45

1. Through right fuel tank opening, separate fuel lines - 1 - and - 2 - for left fuel delivery unit by pressing release buttons.

3 - Right fuel delivery unit with Fuel Pump (FP) G23

1. After separating both fuel lines, pull it out of left fuel tank opening.

Scheme 46

1. Through left fuel tank opening, press release buttons - arrows - and remove fuel delivery line - 2 - and Fuel Level Sensor 3 G237 - 1 -.
2. Swing Fuel Level Sensor 3 G237 aside to left.

Scheme 47

1. Press down both retaining clasps on fuel delivery unit support - arrows -.
2. Remove fuel delivery unit.

Note. Be aware that fuel is still in fuel delivery unit.

Installing

1. Tightening torque --> «Left fuel delivery unit with Transfer Fuel Pump (FP) G6 , Fuel Level Sensor G and Fuel Level Sensor 3 G237 , assembly overview»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system) .

Scheme 48

1. Before installing fuel delivery unit, pull retaining clasps on support upward - arrows - until it engages.
2. Carefully press fuel delivery unit into support until it engages audibly.

1. Insert fuel delivery line - 2 - and Fuel Level Sensor 3 G237 - 1 - until it engages audibly.
2. Feed supply and return lines of left fuel delivery unit through toward right chamber of fuel tank.

1. Through right fuel tank opening, press fuel lines - 1 - and - 2 - on until they engage audibly.

3 - Right fuel delivery unit with Fuel Pump (FP) G23

1. Connect electrical connectors - 1 to 3 - on underside of right locking flange.
2. Install new locking flange seal dry.

Scheme 49

1. Insert locking flange in fuel tank, note installation position

1. The tab - 2 - on locking flange must lie between tabs - 1 - and - 3 - on fuel tank.

1. Tighten locking ring.

1. Install fuel supply line - 2 - and fuel return line - 1 - according to marking until they engage audibly.

1. Connect electrical harness connectors - 1 - and - 2 - to right locking flange.

1. Fasten cover for right locking flange - arrows -.

1. Connect electrical connectors - 1 to 3 - on underside of left locking flange.
2. Install new locking flange seal dry.

1. Insert locking flange in fuel tank, note installation position

1. Tab - 2 - on locking flange must lie between tabs - 1 - and - 3 - on fuel tank.

1. Tighten locking ring.

1. Connect electrical harness connectors - 1 - and - 2 - to left locking flange.

1. Fasten cover for left locking flange - arrows -.
2. Connect battery. Observe safety precautions after connecting battery --> «27 - BATTERY, STARTER, GENERATOR, CRUISE CONTROL»(/audi/s8/d3-2007-2011/remont/cruise-control-systems/#electrical-equipment) .

After installing, fuel vehicle with at least 5 liters of fuel

Scheme 50

1 - Support

1. For fuel delivery unit

2 - Fuel Level Sensor 2 G169

1. Yellow
2. Clipped into mount - 1
3. Resistance values, checking --> «Fuel Level Sensor 2 G169 , checking (right lever sensor)»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__fuel-level-sensor-2-g169)
4. Removing and installing --> «Fuel Level Sensor 2 G169 (right lever sensor), removing and installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__fuel-level-sensor-2-g169-right)

3 - Fuel Level Sensor 4 G393

1. White
2. Clipped onto fuel delivery unit - 14
3. Resistance values, checking --> «Fuel Level Sensor 4 G393 (right tubular sensor), checking»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__fuel-level-sensor-4-g393-right)
4. Removing and installing --> «Fuel Level Sensor 4 G393 (right tubular sensor), removing and installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__fuel-level-sensor-4-g393-right)

4 - Fuel supply line

1. To fuel filter
2. Mark before removing
3. To disconnect, press release button on connection piece
4. Do not kink

1. Clipped in on fuel tank

5 - Fuel return line

1. From fuel rail
2. Mark before removing
3. To disconnect, press release button on connection piece
4. Do not kink

1. Clipped in on fuel tank

6 - Locking ring

1. Use wrench T10202 for removal and installation
2. Tighten to 120 Nm

7 - Seal

1. Replace
2. Install dry

8 - Right locking flange

1. Installed location --> «Installed location of right locking flange»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__installed-location-of-right-locking-flange)

9 - Fuel return line

1. To left fuel delivery unit

10 - Fuel supply line

1. From left fuel delivery unit
2. To disconnect, press release button on connection piece

11 - Suction jet pipe

1. For suction jet pump
2. To disconnect, press release button on connection piece

12 - Fuel delivery line

1. From suction jet pump, left side
2. Clipped onto fuel delivery unit - 14

13 - Fuel filler tube

1. Fuel filler tube
2. Clipped onto fuel delivery unit - 14

14 - Right fuel delivery unit

1. With Fuel Pump (FP) G23
2. Clipped into mount - 1
3. Different versions
4. Fuel pump electrical, checking --> «Fuel Pump (FP) G23 (right), checking electrical»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__fuel-pump-fp-g23-right-checking)

1. Checking residual pressure --> «24 - MULTIPORT FUEL INJECTION (MFI)»(ref-289205-S08445194072008062700000) for 4.2 LITER V8 4V FUEL INJECTION AND IGNITION, ENGINE CODE(S): BVJ 24 MULTIPORT FUEL INJECTION (MFI) for 4.2 LITER V8 5V FUEL INJECTION & IGNITION, ENGINE CODE(S): BFM «24 - MULTIPORT FUEL INJECTION (MFI)»(/audi/s8/d3-2007-2011/remont/cooling-fan/#52l-10-cyl-4v-fuel-injection-ignition-engine-codes-bsm) for 5.2 LITER 10-CYL. 4V FUEL INJECTION IGNITION, ENGINE CODE(S): BSM «24 FUEL INJECTION SYSTEM»(ref-289212-S05463344962008062700000) for 6.0 LITER 12-CYL. 4V FUEL INJECTION AND IGNITION, ENGINE CODE(S): BSB
2. Removing and installing --> «Right fuel delivery unit with Fuel Pump (FP) G23 , removing and installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__right-fuel-delivery-unit-with-fuel)
3. After installing, fuel vehicle with at least 5 liters of fuel

Installed location of right locking flange

1. Install new locking flange seal dry.
2. Insert locking flange in fuel tank, note installation position

1. Tab - 2 - on locking flange must lie between tabs - 1 - and - 3 - on fuel tank.

Fuel Pump (FP) G23 (right), checking electrical

Special tools, testers and auxiliary items required

1. Remote control V.A.G 1348/3A with adapter cable V.A.G 1348/3-2
2. Portable multimeter V.A.G 1526C
3. Connector test set V.A.G 1594C
4. Vehicle Diagnosis, Testing and Information System VAS 5051 with inductive pickup (50 A) VAS 5051/9

Work procedure

1. Battery voltage min. 12.5 V

Scheme 51

1. Fuse - 31 - on fuse panel SC31 (instrument panel, right) O.K.

Scheme 52

1. Fuel Pump (FP) Relay J17 O.K. (on relay and fuse panel in right front footwell), Socket - 4 -.
2. Fuel filter OK.
3. Ignition switched off.

1. Pry off right cover on instrument panel, using a screwdriver - arrow -.

Scheme 53

1. Pull out fuse 31 on fuse panel SC31 (right instrument panel, middle row, first large fuse from top).
2. Connect Remote Control V.A.G 1348/3A with adapter cable V.A.G 1348/3-2 to left socket terminal of fuse SC31.
3. Connect alligator clip on Remote Control V.A.G 1348/3A to battery "+".
4. Press switch on remote control.

1. Operating noise of pump must be audible in vicinity of fuel tank.

Note. Fuel Pump (FP) runs quietly. Avoid surrounding noises while testing fuel pump. If necessary, use a second technician to check.

If no operating noise can be heard

1. Remove trim for luggage compartment floor.

1. Remove cover for right locking flange - arrows -.

Scheme 54

1. Disconnect electrical harness connector - 2 - at right locking flange.

Note. Ignore - 1 -.

1. Connect multimeter between terminal - 1 - and - 4 - of electrical harness connector for voltage measurement.
2. Press switch on remote control.

1. Specified value: approx. battery voltage.

If specification is not obtained

1. Repair wire connection according to wiring diagram.

If specified value is obtained, although no running-noise can be heard at pump

1. Remove right fuel delivery unit --> «Right fuel delivery unit with Fuel Pump (FP) G23 , removing and installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__right-fuel-delivery-unit-with-fuel) .
2. Check if electrical wiring between flange and fuel pump is connected and has continuity.

If no fault is detected in wiring

1. Fuel pump faulty. Replace right fuel delivery unit.
2. Install right fuel delivery unit --> «Installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system) .

1. Voltage supply of Fuel Pump (FP) OK --> «Checking voltage supply»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system) .

1. Pull out fuse 31 on fuse panel SC31 (right instrument panel, middle row, first large fuse from top).

Scheme 55

1. Connect Remote Control V.A.G 1348/3A with adapter cable V.A.G 1348/3-2 to left socket terminal of fuse SC31.
2. Connect alligator clip on Remote Control V.A.G 1348/3A to battery "+".
3. Connect Vehicle Diagnosis, Testing and Information System VAS 5051 with inductive pickup VAS 5051/9 to wire of remote control.
4. Press the switch on the remote control.

1. Measure current draw of fuel pump.

1. Specified value: approx. 8 A

If specification is not obtained

Note. At a displayed current draw of 4 A, Fuel Pump (FP) runs dry.

Right fuel delivery unit with Fuel Pump (FP) G23 , removing and installing

Special tools, testers and auxiliary items required

1. Vehicles from approx. 11/2002: Wrench T10202

Observe safety precautions --> Safety precautions .

Observe rules for cleanliness --> Rules for cleanliness .

1. Remove cover of right luggage compartment side trim - arrows -.

1. Remove cover - 1 - above battery.

Note. Ignore - 2 -.

1. With ignition switched off, disconnect Battery Ground (GND) strap - arrow -.
2. Remove trim for luggage compartment floor.

Note. To remove and install fuel delivery unit, remove vehicle tool kit and spare wheel from luggage compartment. It is then possible to sit or kneel in spare wheel well.

1. Remove cover for right locking flange - arrows -.

1. Disconnect electrical connectors - 1 - and - 2 - at right locking flange.

1. Mark fuel return line - 1 - and fuel supply line - 2 -.

1. Pull both lines from locking flange, by pressing release buttons.

1. Remove locking ring using wrench T10202.

1. Pull off locking flange and remove seal.
2. Disconnect electrical connectors - 1 to 3 - on underside of right locking flange.

Note. To separate the line couplings that are mentioned later in the description, pull fuel lines out of the fuel tank opening. To improve clarity, the following illustration shows several components not installed.

1. Through right fuel tank opening, separate fuel lines - 1 - and - 2 - for left fuel delivery unit by pressing release buttons.

3 - Right fuel delivery unit with Fuel Pump (FP) G23

Scheme 56

1. Unclip filling line from front of right fuel delivery unit - arrow -.

1. Remove cover for left locking flange - arrows -.

1. Disconnect electrical connectors - 1 - and - 2 - at left locking flange.

1. Remove locking ring using wrench T10202.

1. Pull off locking flange and remove seal.
2. Disconnect electrical connectors - 1 to 3 - on underside of left locking flange.

Scheme 57

1. Through left fuel tank opening, separate suction jet pipe - 3 - from Y-piece, by pressing release button.
2. Pull suction jet pipe out toward right fuel tank opening.

Scheme 58

1. Through right fuel tank opening, press release buttons - arrows - and remove fuel delivery line - 2 - and Fuel Level Sensor 4 G393 - 1 -.
2. Swing Fuel Level Sensor 4 G393 aside to right.

1. Press down both retaining clasps on fuel delivery unit support - arrows -.
2. Remove fuel delivery unit.

Note. Be aware that fuel is still in the fuel delivery unit.

1. Tightening torque --> «Right fuel delivery unit with Fuel Pump (FP) G23 , Fuel Level Sensor 2 G169 and Fuel Level Sensor 4 G393 , assembly overview»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system) .

1. Before installing fuel delivery unit, pull retaining clasps on support upward - arrows - until it engages.
2. Carefully press fuel delivery unit into support until it engages audibly.

1. Insert fuel delivery line - 1 - and Fuel Level Sensor 4 G393 - 2 - until it engages audibly on right fuel delivery unit.

1. Through right fuel tank opening, feed suction jet pipe - 3 - toward left chamber of fuel tank.
2. Push suction jet pipe onto Y-piece until it engages audibly.

1. Connect electrical connectors - 1 to 3 - on underside of left locking flange.
2. Install new locking flange seal dry.

1. Insert locking flange in fuel tank, note installation position

1. Tab - 2 - on locking flange must lie between tabs - 1 - and - 3 - on fuel tank.

1. Tighten locking ring.

1. Connect electrical harness connectors - 1 - and - 2 - to left locking flange.

1. Fasten cover for left locking flange - arrows -.

1. Through right fuel tank opening, press fuel lines - 1 - and - 2 - onto left fuel delivery unit until they engage audibly.

3 - Right fuel delivery unit with Fuel Pump (FP) G23

1. Connect electrical connectors - 1 to 3 - on underside of right locking flange.
2. Install new locking flange seal dry.

1. Insert locking flange in fuel tank, note installation position

1. The tab - 2 - on locking flange must lie between tabs - 1 - and - 3 - on fuel tank.

1. Tighten locking ring.

1. Install fuel supply line - 2 - and fuel return line - 1 - according to marking until they engage audibly.

1. Connect electrical harness connectors - 1 - and - 2 - to right locking flange.

1. Fasten cover for right locking flange - arrows -.
2. Connect battery. Observe safety precautions after connecting battery --> «27 - BATTERY, STARTER, GENERATOR, CRUISE CONTROL»(/audi/s8/d3-2007-2011/remont/cruise-control-systems/#electrical-equipment) .

After installing, fuel vehicle with at least 5 liters of fuel

Fuel pump, vehicles with MPI engine and fuel return line, checking delivery quantity

Special tools, testers and auxiliary items required

Scheme 59

1. Pressure gauge K-Jetronic V.A.G 1318
2. Pressure gauge adapter V.A.G 1318/10-12

Scheme 60

1. Remote Control V.A.G 1348/3A with adapter cable V.A.G 1348/3-3
2. Measuring container, fuel-resistant

Work procedure

1. Battery voltage min. 12.5 V.
2. Fuel Pump (FP) Relay J17 O.K. (on relay and fuse panel in right front footwell), Socket - 4 -.

1. Fuel Pump (FP) 2 Relay J49 O.K. (on relay and fuse panel in right of luggage compartment, Socket 3).
2. Fuel filter OK.
3. Fuel tank at least 1 / 4 filled.
4. Ignition switched off.

1. Remove cover of right luggage compartment side trim - arrows -.

1. Remove cover - 2 - above battery.

Note. Ignore - 1 -.

1. Remove trim for luggage compartment floor.
2. Remove cover for left locking flange - arrows -.

1. Disconnect electrical harness connector - 2 - at left locking flange.

Note. Ignore - 1 -.

1. Remove cover for right locking flange - arrows -.

1. Disconnect electrical harness connector - 2 - at right locking flange.

Note. Ignore - 1 -.

Scheme 61

1. Connect Remote Control for VAG 1348 V.A.G 1348/3A with adapter cable V.A.G 1348/3-3 and adapter cables from Connector Test Set V.A.G 1594C to terminal - 4 - (ground) on left and right delivery unit.
2. Route Remote Control V.A.G 1348/3A switch forward in engine compartment.
3. Connect alligator clip to ground point in engine compartment.
4. Connect terminal - 1 - (positive) on left and right delivery unit using a self-made adapter cable to battery "+". For safety reasons, install a fuse - A - (10 A) in wiring.

1. Remove fuel filler cap from fuel filler tube.

Scheme 62

1. Disconnect fuel supply line - 2 - at fuel rail.

Note. Ignore - 1 -.

Scheme 63

1. Connect Fuel Inj. Pressure Gauge-CIS V.A.G 1318 with Adapter V.A.G 1318/11 and V.A.G 1318/12 in fuel line.
2. Connect assisting hose - arrow - on pressure gauge and hold it in a measuring container.
3. Open shut-off valve of pressure gauge set. The lever points in direction of flow.
4. Generate pressure in fuel system by pressing switch of remote control and slowly closing shut-off valve of pressure gauge.

1. Specified value: 4 bar positive pressure.

1. From this point on do not move position of shut-off tap.
2. Empty measuring container.
3. Press switch on remote control for 15 seconds.

Scheme 64

1. Compare quantity of fuel delivered with minimum delivery rate in diagram (cm 3 /15s).

Note. Voltage at fuel pump with engine stopped and pump running is approx. 2 volts less than battery voltage.

If minimum delivery quantity is not obtained, the following malfunctions may be present

1. Fuel lines pinched.
2. Fuel filter clogged.
3. Fuel pump faulty.

Note. Because the quantity of fuel delivered does not decrease significantly when one of the fuel pumps malfunctions - due to the internal lines in the tank - a faulty pump cannot be diagnosed accurately by measuring the quantity delivered.

In this case, proceed as follows

1. Remove electrical adapter cable at each fuel delivery unit.
2. Measure quantity delivered at opposite fuel delivery unit.

If quantity delivered by individually measured fuel delivery unit is considerably less than specified value

1. Replace affected fuel delivery unit.

Assembly is in reverse order of removal, note the following

1. Attach fuel supply line to fuel rail --> «24 - MULTIPORT FUEL INJECTION (MFI)»(ref-289205-S08445194072008062700000) for 4.2 LITER V8 4V FUEL INJECTION AND IGNITION, ENGINE CODE(S): BVJ 24 MULTIPORT FUEL INJECTION (MFI) for 4.2 LITER V8 5V FUEL INJECTION & IGNITION, ENGINE CODE(S): BFM «24 - MULTIPORT FUEL INJECTION (MFI)»(/audi/s8/d3-2007-2011/remont/cooling-fan/#52l-10-cyl-4v-fuel-injection-ignition-engine-codes-bsm) for 5.2 LITER 10-CYL. 4V FUEL INJECTION IGNITION, ENGINE CODE(S): BSM «24 FUEL INJECTION SYSTEM»(ref-289212-S05463344962008062700000) for 6.0 LITER 12-CYL. 4V FUEL INJECTION AND IGNITION, ENGINE CODE(S): BSB .

Fuel pump (vehicles with MPI engine without fuel return line), checking delivery quantity

Special tools, testers and auxiliary items required

1. Adapter V.A.G 1318/26

1. Remote Control V.A.G 1348/3A with adapter cable V.A.G 1348/3-3
2. Measuring container, fuel-resistant

Work procedure

1. Battery voltage min. 12.5 V.

1. Fuel Pump (FP) Relay J17 O.K. (on relay and fuse panel in right front footwell), Socket - 4 -.

1. Fuel Pump (FP) 2 Relay J49 O.K. (on relay and fuse panel in right of luggage compartment, Socket 3).
2. Fuel filter OK.
3. Fuel tank at least 1 / 4 filled.
4. Ignition switched off.

1. Remove cover of right luggage compartment side trim - arrows -.

1. Remove cover - 2 - above battery.

Note. Ignore - 1 -.

1. Remove trim for luggage compartment floor.

1. Remove cover for left locking flange - arrows -.

1. Disconnect electrical harness connector - 2 - at left locking flange.

Note. Ignore - 1 -.

1. Unbolt cover for right locking flange - arrows -.

1. Disconnect electrical harness connector - 2 - at right locking flange.

Note. Ignore - 1 -.

1. Disconnect fuel return line - 1 - from locking flange by pressing release buttons.

Note. Ignore - 2 -.

Scheme 65

1. Connect adapter V.A.G 1318/26 to disconnected fuel line - 1 - and hold it in a measuring container.

1. Connect Remote Control for VAG 1348 V.A.G 1348/3A with adapter cable V.A.G 1348/3-3 and adapter cables from Connector Test Set V.A.G 1594C to terminal - 4 - (ground) on left and right delivery unit.
2. Connect alligator clip to Ground (GND) point near battery.
3. Connect terminal - 1 - (positive) on left and right delivery unit using a self-made adapter cable to battery "+". For safety reasons, install a fuse - A - (10 A) in the wiring.
4. Remove fuel filler cap from fuel filler tube.

1. Press switch on remote control for 15 seconds.

1. Compare quantity of fuel delivered with minimum delivery rate in diagram (cm 3 /15s).

Note. Voltage at fuel pump with engine stopped and pump running is approx. 2 volts less than battery voltage.

If minimum delivery quantity is not obtained, the following malfunctions may be present

1. Fuel lines pinched.
2. Fuel filter clogged.
3. Fuel pumps faulty.

Note. Because the quantity of fuel delivered does not decrease significantly when one of the fuel pumps malfunctions - due to the internal lines in the tank - a faulty pump cannot be diagnosed accurately by measuring the quantity delivered.

In this case, proceed as follows

1. Remove electrical adapter cable at each fuel delivery unit.
2. Measure quantity delivered at opposite fuel delivery unit.

If quantity delivered by individually measured fuel delivery unit is considerably less than specified value

1. Replace affected fuel delivery unit.

Fuel pump (vehicles with 8-cyl. FSI engine), checking delivery rate

Special tools, testers and auxiliary items required

1. Pressure gauge K-Jetronic V.A.G 1318
2. Pressure gauge adapter V.A.G 1318/10-12

1. Remote Control V.A.G 1348/3A with adapter cable V.A.G 1348/3-3
2. Measuring container, fuel-resistant

Scheme 66

Work procedure

1. Battery voltage min. 12.5 V.
2. Fuel Pump (FP) Control Module J538 OK; check in "Guided Fault Finding" with Vehicle Diagnosis, Testing and Information System VAS 5051.
3. Fuel filter OK.
4. Fuel tank at least 1 / 4 filled.

1. Ignition switched off.

1. Remove cover of right luggage compartment side trim - arrows -.

1. Remove cover - 2 - above battery.

Note. Ignore - 1 -.

1. Remove trim for luggage compartment floor.

1. Remove cover for left locking flange - arrows -.

1. Disconnect electrical harness connector - 2 - at left locking flange.

Note. Ignore - 1 -.

1. Remove cover for right locking flange - arrows -.

1. Disconnect electrical harness connector - 2 - at right locking flange.

Note. Ignore - 1 -.

1. Connect Remote Control for VAG 1348 V.A.G 1348/3A with adapter cable V.A.G 1348/3-3 and adapter cables from Connector Test Set V.A.G 1594C to terminal - 4 - (ground) on left and right delivery unit.
2. Route Remote Control V.A.G 1348/3A switch forward in engine compartment.
3. Connect alligator clip to Ground (GND) point in engine compartment.
4. Connect terminal - 1 - (positive) on left and right delivery unit using a self-made adapter cable to battery "+". For safety reasons, install a fuse - A - (10 A) in wiring.

1. Remove fuel filler cap from fuel filler tube.

Scheme 67

1. Pull rear engine cover - arrows - off.

Scheme 68

1. Disconnect fuel supply line - arrow - on distribution piece.

1. Disconnect fuel line - arrow -.

1. Connect Fuel Inj. Pressure Gauge-CIS V.A.G 1318 with Adapter V.A.G 1318/11 and V.A.G 1318/12 in fuel line.
2. Connect assisting hose - arrow - on pressure gauge and hold it in a measuring container.
3. Open shut-off valve of pressure gauge set. The lever points in direction of flow.
4. Generate pressure in fuel system by pressing switch of remote control and slowly closing shut-off valve of pressure gauge.

1. Specified value: 4 bar positive pressure.

1. From this point on do not move position of shut-off tap.
2. Empty measuring container.
3. Press switch on remote control for 15 seconds.

Scheme 69

1. Compare quantity of fuel delivered with minimum delivery rate in diagram (cm 3 /15s).

Note. Voltage at fuel pump with engine stopped and pump running is approx. 2 volts less than battery voltage.

If minimum delivery quantity is not obtained, the following malfunctions may be present

1. Fuel lines pinched.
2. Fuel filter clogged.
3. Fuel pump faulty.

Note. Because the quantity of fuel delivered does not decrease significantly when one of the fuel pumps malfunctions - due to the internal lines in the tank - a faulty pump cannot be diagnosed accurately by measuring the quantity delivered.

In this case, proceed as follows

1. Remove electrical adapter cable at each fuel delivery unit.
2. Measure quantity delivered at opposite fuel delivery unit.

If quantity delivered by individually measured fuel delivery unit is considerably less than specified value

1. Replace affected fuel delivery unit.

Assembly is in reverse order of removal, note the following

1. Attach fuel line to engine --> «24 - MULTIPORT FUEL INJECTION (MFI)»(ref-289205-S08445194072008062700000) for 4.2 LITER V8 4V FUEL INJECTION AND IGNITION, ENGINE CODE(S): BVJ 24 MULTIPORT FUEL INJECTION (MFI) for 4.2 LITER V8 5V FUEL INJECTION & IGNITION, ENGINE CODE(S): BFM «24 - MULTIPORT FUEL INJECTION (MFI)»(/audi/s8/d3-2007-2011/remont/cooling-fan/#52l-10-cyl-4v-fuel-injection-ignition-engine-codes-bsm) for 5.2 LITER 10-CYL. 4V FUEL INJECTION IGNITION, ENGINE CODE(S): BSM «24 FUEL INJECTION SYSTEM»(ref-289212-S05463344962008062700000) for 6.0 LITER 12-CYL. 4V FUEL INJECTION AND IGNITION, ENGINE CODE(S): BSB .

Fuel pump (vehicles with 10-cyl. engine (Audi S8)), checking delivery rate

Special tools, testers and auxiliary items required

1. Pressure gauge K-Jetronic V.A.G 1318
2. Pressure gauge adapter V.A.G 1318/10-12

1. Remote Control V.A.G 1348/3A with adapter cable V.A.G 1348/3-3
2. Measuring container, fuel-resistant

Work procedure

1. Battery voltage min. 12.5 V.
2. Fuel Pump (FP) Control Module J538 OK; check in "Guided Fault Finding" with Vehicle Diagnosis, Testing and Information System VAS 5051.
3. Fuel filter OK.
4. Fuel tank at least 1 / 4 filled.

1. Ignition switched off.

1. Remove cover of right luggage compartment side trim - arrows -.

1. Remove cover - 2 - above battery.

Note. Ignore - 1 -.

1. Remove trim for luggage compartment floor.
2. Remove cover for left locking flange - arrows -.

1. Disconnect electrical harness connector - 2 - at left locking flange.

Note. Ignore - 1 -.

1. Remove cover for right locking flange - arrows -.

1. Disconnect electrical harness connector - 2 - at right locking flange.

Note. Ignore - 1 -.

1. Connect Remote Control for VAG 1348 V.A.G 1348/3A with adapter cable V.A.G 1348/3-3 and adapter cables from Connector Test Set V.A.G 1594C to terminal - 4 - (ground) on left and right delivery unit.
2. Route Remote Control V.A.G 1348/3A switch forward in engine compartment.
3. Connect alligator clip to Ground (GND) point in engine compartment.
4. Connect terminal - 1 - (positive) on left and right delivery unit using a self-made adapter cable to battery "+". For safety reasons, install a fuse - A - (10 A) in wiring.

1. Remove fuel filler cap from fuel filler tube.

Scheme 70

1. Remove rear engine cover - 2 - - arrows -.

Note. Ignore - 1 -.

Scheme 71

1. Disconnect fuel line - arrow - on fuel rail.

Scheme 72

1. Connect Fuel Inj. Pressure Gauge-CIS V.A.G 1318 with Adapter V.A.G 1318/11 and V.A.G 1318/12 in fuel line.
2. Connect assisting hose - arrow - on pressure gauge and hold it in a measuring container.
3. Open shut-off valve of pressure gauge set. The lever points in direction of flow.
4. Generate pressure in fuel system by pressing switch of remote control and slowly closing shut-off valve of pressure gauge.

1. Specified value: 4 bar positive pressure.

1. From this point on do not move position of shut-off tap.
2. Empty measuring container.
3. Press switch on remote control for 15 seconds.

1. Compare quantity of fuel delivered with minimum delivery rate in diagram (cm 3 /15s).

Note. Voltage at fuel pump with engine stopped and pump running is approx. 2 volts less than battery voltage.

If minimum delivery quantity is not obtained, the following malfunctions may be present

1. Fuel lines pinched.
2. Fuel filter clogged.
3. Fuel pump faulty.

Note. Because the quantity of fuel delivered does not decrease significantly when one of the fuel pumps malfunctions - due to the internal lines in the tank - a faulty pump cannot be diagnosed accurately by measuring the quantity delivered.

In this case, proceed as follows

1. Remove electrical adapter cable at each fuel delivery unit.
2. Measure quantity delivered at opposite fuel delivery unit.

If quantity delivered by individually measured fuel delivery unit is considerably less than specified value

1. Replace affected fuel delivery unit.

Assembly is in reverse order of removal, note the following

1. Attach fuel line to fuel rail --> «24 - MULTIPORT FUEL INJECTION (MFI)»(ref-289205-S08445194072008062700000) for 4.2 LITER V8 4V FUEL INJECTION AND IGNITION, ENGINE CODE(S): BVJ 24 MULTIPORT FUEL INJECTION (MFI) for 4.2 LITER V8 5V FUEL INJECTION & IGNITION, ENGINE CODE(S): BFM «24 - MULTIPORT FUEL INJECTION (MFI)»(/audi/s8/d3-2007-2011/remont/cooling-fan/#52l-10-cyl-4v-fuel-injection-ignition-engine-codes-bsm) for 5.2 LITER 10-CYL. 4V FUEL INJECTION IGNITION, ENGINE CODE(S): BSM «24 FUEL INJECTION SYSTEM»(ref-289212-S05463344962008062700000) for 6.0 LITER 12-CYL. 4V FUEL INJECTION AND IGNITION, ENGINE CODE(S): BSB .

Scheme 73

1 - Left suction jet pump

2 - Left fuel delivery unit

3 - Expansion tank

4 - Right fuel pump

5 - Right fuel delivery unit

6 - Right suction jet pump

7 - Y-fitting

8 - Y-fitting

Description of function

To make sure that fuel is supplied in all driving situations, the fuel pumps must absolutely never take on air, even under hard braking and cornering situations. This risk is a possibility for any partially-filled fuel tank, when all the fuel swashes into a corner of the fuel tank.

1. Therefore, the fuel delivery units - 2 - and - 5 - not only consist of respective fuel pumps, but also an appropriately named baffle housing, into which pumps are inserted. The baffle housing is a container that is steadily filled with fuel so that the fuel pumps are always surrounded by fuel, independent of the fuel level in fuel tank.
2. It is understandable that the trouble-free function of the fuel pumps is dependent on filling of baffle housing. This is what the appropriately named suction jet pumps are for.
3. Function of the suction jet pumps is based on a simple physical principle: A suction jet from right fuel pump supply pipe - 4 - is compressed by a nozzle in suction jet pumps - 1 - and - 6 - and is thereby accelerated. This acceleration causes surrounding fuel to be drawn in and be forced to baffle housings of fuel delivery units. The right suction jet pump - 6 - supplies left baffle housing and left suction jet pump - 1 - supplies right baffle housing.
4. The fuel is distributed from supply pipe for fuel pump (right side) to two suction jet pumps via 2 Y-connectors - 7 - and - 8 -.

1. Another smaller suction jet pump is located in reservoir - 3 - and pumps available fuel back into fuel tank.

Left suction jet pump, removing and installing

Removing

Observe safety precautions --> Safety precautions .

Observe rules for cleanliness --> Rules for cleanliness .

1. Remove left fuel delivery unit --> «Left fuel delivery unit with Transfer Fuel Pump (FP) G6 , removing and installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__left-fuel-delivery-unit-with-transfer) .
2. Remove left Fuel Level Sensor 3 G237 (tubular sensor) out of fuel tank.

1. Through left fuel tank opening, separate suction jet pipes - 1 - and - 3 - from Y-piece, by pressing release button.

1. Through right fuel tank opening, press release buttons - arrows - and remove fuel delivery line - 1 -.

Note. Ignore - 2 -.

1. Pull fuel delivery line out through left fuel tank opening.

Scheme 74

1. Through left fuel tank opening, press release button - arrow - and pull bracket for suction jet pipes from mounting.
2. Pull left suction jet pipe with lines out toward left fuel tank opening.

Installing

Scheme 75

1. Set left suction jet pump - 1 - into fuel tank so that is positioned in recess of front fuel tank baffle plate - 2 - , as shown in illustration.
2. Press suction jet pump bracket into mount until it engages audibly.
3. Feed delivery line through left fuel tank opening into right chamber of fuel tank. Observe routing

1. The fuel delivery line - 3 - must be routed under fuel filling line - 2 - in area of left fuel tank opening.

Note. Ignore - 1 -.

1. Press fuel delivery line - 1 - onto right fuel delivery unit until it engages audibly.

Note. Ignore - 2 -.

1. Through left fuel tank opening, push suction jet lines - 1 - and - 3 - onto Y-fitting until they engage audibly.
2. Insert Fuel Level Sensor 3 G237 in fuel tank.
3. Install left fuel delivery unit --> «Installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__installing) .

Right suction jet pump, removing and installing

Removing

Observe safety precautions --> Safety precautions .

Observe rules for cleanliness --> Rules for cleanliness .

1. Remove right fuel delivery unit --> «Right fuel delivery unit with Fuel Pump (FP) G23 , removing and installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__right-fuel-delivery-unit-with-fuel) .
2. Remove right Fuel Level Sensor 4 G393 (tubular sensor) out of fuel tank.

1. Through left fuel tank opening, separate suction jet pipe - 5 - from Y-piece, by pressing release button.

1. Through left fuel tank opening, press release buttons - arrows - and remove fuel delivery line - 2 -.

Note. Ignore - 1 -.

1. Pull fuel delivery line out through right fuel tank opening.

Scheme 76

1. Through right fuel tank opening, press release button - arrow - and pull bracket for suction jet pipes from mounting.
2. Pull right suction jet pipe with lines out toward right fuel tank opening.

Installing

1. Set right suction jet pump - 1 - into fuel tank so that is positioned in recess of front fuel tank baffle plate - 2 - , as shown in illustration.
2. Press suction jet pump bracket into mount until it engages audibly.
3. Feed fuel delivery line through the right fuel tank opening into left chamber of fuel tank. Observe routing

1. The fuel delivery line - 1 - must be routed under fuel filling line - 2 - in area of left fuel tank opening.

Note. Ignore - 3 -.

1. Press fuel delivery line - 2 - onto left fuel delivery unit until it engages audibly.

Note. Ignore - 1 -.

1. Through right fuel tank opening, feed suction jet pipe - 5 - toward left chamber of fuel tank.
2. Push suction jet pipe onto Y-piece until it engages audibly.
3. Insert Fuel Level Sensor 4 G393 in fuel tank.
4. Install right fuel delivery unit --> «Installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system) .

Fuel Level Sensor G , checking (left lever-type sensor)

Special tools, testers and auxiliary items required

Scheme 77

1. Portable multimeter V.A.G 1526C

Scheme 78

1. Connector test set V.A.G 1594C

Work procedure

1. Remove trim for luggage compartment floor.

1. Remove cover for left locking flange - arrows -.

1. Disconnect electrical harness connector - 1 - at left locking flange.

Note. Ignore - 2 -.

Scheme 79

1. Connect multimeter between terminal - 2 - and - 4 - of connector - B - for resistance measurement.

Note. If measured value is 0 ohms there is a short circuit. If measured value is infinity ohms there is and open circuit in the wiring. To check resistance values "tank full" or "tank empty" , the Fuel Level Sensor G must be removed --> Fuel Level Sensor G (left lever-type sensor), removing and installing and the floater of the sensor must be placed in upper or lower end position. With fuel level sensor G removed, the following values are obtained because of the greater deflection of the floater arm

Fuel Level Sensor G (left lever-type sensor), removing and installing

Observe safety precautions --> Safety precautions .

Observe rules for cleanliness --> Rules for cleanliness .

1. Remove left fuel delivery unit --> «Left fuel delivery unit with Transfer Fuel Pump (FP) G6 , removing and installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__left-fuel-delivery-unit-with-transfer) .
2. Remove left Fuel Level Sensor 3 G237 (tubular sensor) out of fuel tank.

Scheme 80

1. Release Fuel Level Sensor G - arrow - and pull it off from mounting.

Installing

1. Insert Fuel Level Sensor G into mount until it engages audibly.
2. Insert Fuel Level Sensor 3 G237 in fuel tank.
3. Install left fuel delivery unit --> «Installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__installing) .

Fuel Level Sensor 2 G169 , checking (right lever sensor)

Special tools, testers and auxiliary items required

1. Portable multimeter V.A.G 1526C

1. Connector test set V.A.G 1594C

Work procedure

1. Remove trim for luggage compartment floor.

1. Remove cover for right locking flange - arrows -.

1. Disconnect electrical harness connector - 1 - at right locking flange.

Note. Ignore - 2 -.

Scheme 81

1. Connect multimeter between terminal - 2 - and - 4 - of connector - B - for resistance measurement.

Note. If measured value is 0 ohms there is a short circuit. If measured value is infinity ohms there is and open circuit in the wiring. To check resistance values "tank full" or "tank empty" , the Fuel Level Sensor 2 G169 must be removed --> Fuel Level Sensor 2 G169 (right lever sensor), removing and installing and the sensor floater must be placed in upper or lower end position. With Fuel Level Sensor 2 G169 removed, the following values are obtained because of the greater deflection of the floater arm

Fuel Level Sensor 2 G169 (right lever sensor), removing and installing

Removing

Observe safety precautions --> Safety precautions .

Observe rules for cleanliness --> Rules for cleanliness .

1. Remove right fuel delivery unit --> «Right fuel delivery unit with Fuel Pump (FP) G23 , removing and installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__right-fuel-delivery-unit-with-fuel) .
2. Remove right Fuel Level Sensor 4 G393 (tubular sensor) out of fuel tank.

Scheme 82

1. Release Fuel Level Sensor 2 G169 - arrow - and pull it off from mounting.

Installing

1. Insert Fuel Level Sensor 2 G169 in mount until it engages audibly.
2. Insert Fuel Level Sensor 4 G393 in fuel tank.
3. Install right fuel delivery unit --> «Installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system) .

Fuel Level Sensor 3 G237 , checking (left tubular sensor)

Special tools, testers and auxiliary items required

1. Portable multimeter V.A.G 1526C

1. Connector test set V.A.G 1594C

Work procedure

1. Remove trim for luggage compartment floor.

1. Remove cover for left locking flange - arrows -.

1. Disconnect electrical harness connector - 2 - at left locking flange.

Note. Ignore - 1 -.

1. Connect multimeter between terminal - 2 - and - 3 - of connector - A - for resistance measurement.

Note. If measured value is 0 ohms there is a short circuit. If measured value is infinity ohms there is and open circuit in the wiring. To check resistance values "tank full" or "tank empty" , the Fuel Level Sensor 3 G237 must be removed --> Fuel Level Sensor 3 G237 (left tubular sensor), removing and installing and the sensor floater must be allowed to float to upper or lower end position.

Fuel Level Sensor 3 G237 (left tubular sensor), removing and installing

Special tools, testers and auxiliary items required

1. Vehicles from approx. 11/2002: Wrench T10202

Removing

Observe safety precautions --> Safety precautions .

Observe rules for cleanliness --> Rules for cleanliness .

1. Remove cover of right luggage compartment side trim - arrows -.

1. Remove cover - 1 - above battery.

Note. Ignore - 2 -.

1. With ignition switched off, disconnect Battery Ground (GND) strap - arrow -.
2. Open fuel filler flap briefly and then close again.
3. Remove trim for luggage compartment floor.

Note. To remove and install the tubular sensor, remove vehicle tool kit and spare wheel from luggage compartment. It is then possible to sit or kneel in spare wheel well.

1. Remove cover for left locking flange - arrows -.

1. Disconnect electrical connectors - 1 - and - 2 - at left locking flange.

1. Remove locking ring using wrench T10202.

1. Pull off locking flange and remove seal.
2. Disconnect electrical connectors - 1 to 3 - on underside of left locking flange.

1. Through left fuel tank opening, press release buttons - arrows - and remove fuel delivery line - 2 - and Fuel Level Sensor 3 G237 - 1 -.
2. Swing Fuel Level Sensor 3 G237 aside to left.

1. Press down both retaining clasps on fuel delivery unit support - arrows -.
2. Pull fuel rail upward slightly and remove Fuel Level Sensor 3 G237 at same time.

Note. Note that there is still fuel in Fuel Level Sensor 3 G237.

Installing

1. Tightening torques --> «Left fuel delivery unit with Transfer Fuel Pump (FP) G6 , Fuel Level Sensor G and Fuel Level Sensor 3 G237 , assembly overview»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system) .

1. Before installing fuel delivery unit, pull retaining clasps on support upward - arrows - until it engages.
2. Carefully press fuel delivery unit into support until it engages audibly.

1. Insert fuel delivery line - 2 - and Fuel Level Sensor 3 G237 - 1 - until it engages audibly.

1. Connect electrical connectors - 1 to 3 - on underside of left locking flange.
2. Install new locking flange seal dry.

1. Insert locking flange in fuel tank, note installation position

1. Tab - 2 - on locking flange must lie between tabs - 1 - and - 3 - on fuel tank.

1. Tighten locking ring.

1. Connect electrical harness connectors - 1 - and - 2 - to left locking flange.

1. Fasten cover for left locking flange - arrows -.
2. Connect battery. Observe safety precautions after connecting battery --> «27 - BATTERY, STARTER, GENERATOR, CRUISE CONTROL»(/audi/s8/d3-2007-2011/remont/cruise-control-systems/#electrical-equipment) .

Fuel Level Sensor 4 G393 (right tubular sensor), checking

Special tools, testers and auxiliary items required

1. Portable multimeter V.A.G 1526C

1. Connector test set V.A.G 1594C

Work procedure

1. Remove trim for luggage compartment floor.

1. Remove cover for right locking flange - arrows -.

1. Disconnect electrical harness connector - 2 - at right locking flange.

Note. Ignore - 1 -.

1. Connect multimeter between terminal - 2 - and - 3 - of connector - A - for resistance measurement.

Note. If measured value is 0 ohms there is a short circuit. If measured value is infinity ohms there is and open circuit in wiring. To check resistance values "tank full" or "tank empty" , the Fuel Level Sensor 4 G393 must be removed --> Fuel Level Sensor 4 G393 (right tubular sensor), removing and installing and the sensor floater must be allowed to float to upper or lower end position.

Fuel Level Sensor 4 G393 (right tubular sensor), removing and installing

Special tools, testers and auxiliary items required

1. Wrench T10202

Removing

Observe safety precautions --> Safety precautions .

Observe rules for cleanliness --> Rules for cleanliness .

1. Remove cover of right luggage compartment side trim - arrows -.

1. Remove cover - 1 - above battery.

Note. Ignore - 2 -.

1. With ignition switched off, disconnect Battery Ground (GND) strap - arrow -.
2. Open fuel filler flap briefly and then close again.

1. Remove trim for luggage compartment floor.

Note. To remove and install the tubular sensor, remove vehicle tool kit and spare wheel from luggage compartment. It is then possible to sit or kneel in spare wheel well.

1. Remove cover for right locking flange - arrows -.

1. Disconnect electrical connectors - 1 - and - 2 - at right locking flange.

1. Mark fuel return line - 1 - and fuel supply line - 2 -.

1. Pull both lines from locking flange, by pressing release buttons.

1. Remove locking ring with wrench T10202.

1. Pull off locking flange and remove seal.
2. Separate electrical connectors - 1 to 3 - on underside of right locking flange.

Note. To separate the line couplings that are mentioned later in the description, pull fuel lines out of the fuel tank opening. To improve clarity, the following illustration shows several components not installed.

1. Through right fuel tank opening, separate fuel lines - 1 - and - 2 - for left fuel delivery unit by pressing release buttons.

3 - Right fuel delivery unit with Fuel Pump (FP) G23

1. Through right fuel tank opening, press release buttons - arrows - and remove fuel delivery line - 2 - and Fuel Level Sensor 4 G393 - 1 -.
2. Swing Fuel Level Sensor 4 G393 aside to right.

1. Press down both retaining clasps on fuel delivery unit support - arrows -.
2. Pull fuel rail upward slightly and remove Fuel Level Sensor 4 G393 at the same time.

Note. Note that there is still fuel in Fuel Level Sensor 4 G393.

Installing

1. Tightening torques --> «Right fuel delivery unit with Fuel Pump (FP) G23 , Fuel Level Sensor 2 G169 and Fuel Level Sensor 4 G393 , assembly overview»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system) .

1. Before installing fuel delivery unit, pull retaining clasps on support upward - arrows - until it engages.
2. Carefully press fuel delivery unit into support until it engages audibly.

1. Insert fuel delivery line - 1 - and Fuel Level Sensor 4 G393 - 2 - until it engages audibly.

1. Through right fuel tank opening, press fuel lines - 1 - and - 2 - onto left fuel delivery unit until they engage audibly.

3 - Right fuel delivery unit with Fuel Pump (FP) G23

1. Connect electrical connectors - 1 to 3 - on underside of right locking flange.
2. Install new locking flange seal dry.

1. Insert locking flange in fuel tank, note installation position

1. The tab - 2 - on locking flange must lie between tabs - 1 - and - 3 - on fuel tank.

1. Tighten locking ring.

1. Install fuel supply line - 2 - and fuel return line - 1 - according to marking until they engage audibly.

1. Connect electrical harness connectors - 1 - and - 2 - to right locking flange.

1. Fasten cover for right locking flange - arrows -.
2. Connect battery. Observe safety precautions after connecting battery --> «27 - BATTERY, STARTER, GENERATOR, CRUISE CONTROL»(/audi/s8/d3-2007-2011/remont/cruise-control-systems/#electrical-equipment) .

Scheme 83

1 - Fuel return line

1. From engine
2. Clipped into fuel filter bracket
3. To disconnect, press release button on connection piece

2 - Fuel filter

1. Direction of flow is marked with arrows
2. Do not interchange connections
3. Removing and installing --> «Fuel filter for vehicles without auxiliary heater, removing and installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__fuel-filter-for-vehicles-without-auxiliary)

3 - Fuel supply line

1. From fuel tank
2. To disconnect, press release button on connection piece

4 - Bracket for fuel filter

5 - 1.5 Nm

6 - Fuel supply line

1. To engine
2. To disconnect, press release button on connection piece

7 - 3 Nm

Fuel filter for vehicles without auxiliary heater, removing and installing

Special tools, testers and auxiliary items required

1. Drip tray

Removing

Observe safety precautions --> Safety precautions .

Observe rules for cleanliness --> Rules for cleanliness .

1. Remove right cover - 1 - from bottom of vehicle floor.

Scheme 84

1. Place drip tray under fuel filter.

1. Disconnect fuel lines - 1 - and - 3 - by pressing release button.
2. Remove bolts - 2 -.
3. Remove fuel filter.

Installing

1. Tightening torque --> «Fuel filter for vehicles without auxiliary heater, assembly overview»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system) .

Installation is in reverse order of removal, note the following

1. Direction of flow is marked with arrows.

Scheme 85

1 - Fuel return line

1. From engine
2. Clipped into fuel filter bracket
3. To disconnect, press release button on connection piece

2 - Fuel filter

1. Direction of flow is marked with arrows
2. Do not interchange connections
3. Removing and installing --> «Fuel filter for vehicles with auxiliary heater, removing and installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__fuel-filter-for-vehicles-with-auxiliary)

3 - Fuel supply line

1. From fuel tank
2. To disconnect, press release button on connection piece

4 - Fuel supply line

1. To metering pump for auxiliary heater

5 - 10 Nm

1. Self-locking
2. Replace

6 - Washer

7 - Support

1. For metering pump of auxiliary heater

8 - Auxiliary heater metering pump

1. Secure on bracket - 10 - with mount - 7

9 - Fuel supply line

1. To auxiliary heater

10 - Bracket for fuel filter

11 - 1.5 Nm

12 - Fuel supply line

1. To engine
2. To disconnect, press release button on connection piece

13 - 3 Nm

Fuel filter for vehicles with auxiliary heater, removing and installing

Special tools, testers and auxiliary items required

1. Drip tray

Removing

Observe safety precautions --> Safety precautions .

Observe rules for cleanliness --> Rules for cleanliness .

1. Remove right cover - 1 - from bottom of vehicle floor.

1. Place drip tray under fuel filter.

1. Disconnect fuel lines - 1 - and - 3 - by pressing release button.
2. Remove bolts - 2 -.
3. Remove fuel filter.

Installing

1. Tightening torque --> «Fuel filter for vehicles with auxiliary heater, assembly overview»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system) .

Installation is in reverse order of removal, note the following

1. Direction of flow is marked with arrows.

Scheme 86

1 - Fuel filter with pressure regulator (4 bar)

1. Direction of flow is marked with arrows
2. Do not interchange connections
3. Removing and installing --> «Fuel filter for vehicles without fuel system return line, removing and installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__fuel-filter-for-vehicles-without-fuel)

2 - Fuel supply line

1. From fuel tank
2. To disconnect, press release button on connection piece

3 - Fuel return line

1. To fuel tank
2. To disconnect, press release button on connection piece

4 - Bracket for fuel filter

5 - 1.5 Nm

6 - Fuel line

1. To engine
2. To disconnect, press release button on connection piece

7 - 3 Nm

Fuel filter for vehicles without fuel system return line, removing and installing

Special tools, testers and auxiliary items required

1. Drip tray

Removing

Observe safety precautions --> Safety precautions .

Observe rules for cleanliness --> Rules for cleanliness .

1. Remove right cover - 1 - from bottom of vehicle floor.

Scheme 87

1. Place drip tray under fuel filter.

1. Disconnect fuel lines - 1 - , - 2 - and - 4 - by pressing release button.
2. Remove bolts - 3 -.
3. Remove fuel filter.

Installing

1. Tightening torque --> «Fuel filter for vehicles without fuel system return line, assembly overview»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system)

Installation is in reverse order of removal, note the following

1. Direction of flow is marked with arrows.

Scheme 88

1 - EVAP canister cover

2 - Vent line

1. To Evaporative Emission (EVAP) Canister Purge Regulator Valve N80

3 - Vent line

1. To fuel tank

4 - EVAP canister

1. Component location: In bottom of spare wheel well on vehicle floor

5 - Connecting hose

1. Leak detection pump/EVAP canister

6 - Bushing

7 - Rubber grommet

8 - Stud bolt, 16 Nm

9 - Cap nut, 9 Nm

Evaporative emissions (EVAP) canister, removing and installing

Note. Checking for leaks --> Diagnostic leak test, performing .

Removing

Observe safety precautions --> Safety precautions .

Observe rules for cleanliness --> Rules for cleanliness .

Scheme 89

1. Remove EVAP canister cover at bottom of spare wheel well - arrows -.
2. Disconnect hose connections - 1 to 3 - at vent lines.

Scheme 90

1. Remove stud bolts - arrows - and remove EVAP canister.

Installing

1. Tightening torques --> «EVAP canister system, assembly overview»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system) .

Installation is in reverse order of removal, note the following

Note. Secure all hose connections using hose clamps appropriate for the model type .

Scheme 91

1 - Throttle valve control module J338

2 - Evaporative Emission (EVAP) Canister Purge Solenoid Valve N80

1. Component location: In engine compartment

3 - Vent line

1. From EVAP canister to Evaporative Emission (EVAP) Canister Purge Regulator Valve N80
2. Installed location: At right beneath vehicle floor

4 - Vent line

1. To fuel tank

5 - EVAP canister

1. Component location: In bottom of spare wheel well on vehicle floor

6 - Connecting hose

1. Leak detection pump/EVAP canister
2. Pressure side

7 - Evaporative emission (EVAP) canister purge solenoid valve N115

1. Component location: In left rear wheel housing behind wheel housing liner

8 - Leak detection pump (LDP) V144

1. Driven by vacuum
2. Component location: In left rear wheel housing behind wheel housing liner

9 - Air filter for diagnosis pump

1. Installed location: Arrow on filter housing points toward detection pump - 8

10 - Vacuum line

1. Delivers vacuum from intake manifold to detection pump drive

Scheme 92

1 - Intake manifold

2 - Evaporative Emission (EVAP) Canister Purge Solenoid Valve N80

1. Component location: In engine compartment

3 - Evaporative Emission (EVAP) Canister Purge Regulator Valve 2 N333

1. Component location: In engine compartment

4 - Vent line

1. From EVAP canister to EVAP canister purge regulator valves in engine compartment
2. Installed location: At right beneath vehicle floor

5 - Vent line

1. To fuel tank

6 - EVAP canister

1. Component location: In bottom of spare wheel well on vehicle floor

7 - Connecting hose

1. Leak detection pump/EVAP canister
2. Pressure side

8 - Evaporative emission (EVAP) canister purge solenoid valve N115

1. Component location: In left rear wheel housing behind wheel housing liner

9 - Leak detection pump (LDP) V144

1. Driven by vacuum
2. Component location: In left rear wheel housing behind wheel housing liner

10 - Air filter for diagnosis pump

1. Installed location: Arrow on filter housing points toward detection pump - 9

11 - Vacuum line

1. Delivers vacuum from intake manifold to detection pump drive

Leak detection system

Function

The leak detection system recognizes leaks in the complete fuel system, including fuel tank, EVAP canister and Evaporative Emission (EVAP) Canister Purge Regulator Valve N80.

On the mechanical side, the leak detection system consists mainly of a vacuum-driven diaphragm pump, that is equipped with a reed contact on the actuation rod of the pump diaphragm. The pump is supplied with vacuum via engine intake stroke.

1. When leak detection is activated, the diaphragm pump pumps fuel system up to 20 to 30 mbar. The pump membrane is then moved outward, thereby setting the reed contact at the actuation rod to "open" position.
2. During leak diagnosis, the reed contact is monitored to check if it remains open within 10 seconds. This indicates the system is sealed.
3. If pressure falls (indicating a leak), the diaphragm moves back and the reed contact closes.
4. If reed contact closes within 10 seconds of leak detection time, a further test is performed: In this case the diaphragm pump pumps 4 times again. The engine control module (ECM) measures the time for each of the 4 pumps until the reed contact is closed again. From that, the control module can recognize a "small leak" (smaller than 1 mm in diameter) or a "large leak".

Leak diagnostic is activated automatically shortly following every engine start. If a malfunction is determined, an entry is made to the DTC memory. The Malfunction Indicator Lamp (MIL) in the instrument cluster lights up if the malfunction is recognized for 2 subsequent starts. Leak diagnosis can also be activated using Vehicle Diagnosis, Testing and Information System VAS 5051 --> Diagnostic leak test, performing .

Automatic leak detection system

With engine running, the engine control module may perform a leak diagnosis at specific intervals.

It can be determined if an automatic leak diagnosis was recently performed by using Vehicle Diagnosis, Testing and Information System VAS 5051 in measured value block 071 --> Diagnostic leak test, performing .

Diagnostic leak test, performing

Special tools, testers and auxiliary items required

Scheme 93

1. Vehicle diagnostic, testing, and information system VAS 5051 (VAS 5051 B version shown as example only)

Work procedure

1. Electrical parking brake activated.
2. Vehicles with manual transmission: Shift lever in neutral.
3. Vehicles with automatic transmission: Selector lever in "P" or "N".
4. Engine running at idle.

1. Electrical consumers switched off (Radiator fan must not run during test).
2. Air conditioning system switched off.

Scheme 94

1. Vehicle Diagnosis, Testing and Information System VAS 5051 connected, On-board diagnostics and vehicle system "01 Engine electronics" selected.
2. No faults in DTC memory.
3. Intake air temperature less than 90° C --> Measuring value block 004, display field 4.
4. Coolant temperature less than 95° C --> Measuring value block 004, display field 3.

1. Throttle valve angle less than 10° --> Measuring value block 003, display field 3.

Observe safety precautions --> Safety precautions .

Observe rules for cleanliness --> Rules for cleanliness .

Note. Secure all hose connections using hose clamps appropriate for the model type . Replace seals and gaskets when performing repair work.

Scheme 95

Display on VAS 5051

1. Tap "On Board Diagnostic" in selection - 1 - and activate by tapping --> button.

Scheme 96

Display on VAS 5051

1. Tap "01 - Engine Electronics" vehicle system in selection - 1 - and activate by tapping --> button.

Scheme 97

Display on VAS 5051

1. Tap "006 - Basic Setting" function in selection - 1 - and activate by pressing --> button.

Scheme 98

Display on VAS 5051

1. In button field - 1 - , press buttons 7 1 for "display group 071" and confirm entry by pressing Q button.

Scheme 99

Display on VAS 5051

1. Check reading in display field - 1 -.

1. Specified value: "Reed closed".

Note. If "Reed closed" is displayed, continue test. If the reading on the display shows "Reed open" : Briefly open cap of the fuel tank to relieve pressure - thereby the reed contact will close again.

Scheme 100

1. Activate basic setting by pressing Activate button - A -.

Display on VAS 5051

1. Check reading in display field - 4 -.

1. Specified value: "Test ON".

The system test takes several minutes.

1. Check reading in display field - 4 -.

1. Specified value: "Syst.O.K.".

The system is sealed, test is ended.

1. End function "006 - Basic setting" by pressing <-- button.

Fault indication

If a malfunction was recognized during system test, malfunction is indicated afterward.

On VAS 5051 display in display field - 4

1. In case of malfunction: Syst. O.K..

1. Check readings of diagnosis in display field - 2 -.

1. "Small leak" or "Large leak".

1. End function "006 - Basic setting" by pressing <-- button.

If system has recognized a small or large leak

1. Check fuel supply and tank ventilation systems for leaks --> «Checking fuel supply and tank ventilation systems for leaks»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__checking-fuel-supply-and-tank-ventilation) .
2. Afterwards, perform leak diagnosis again.

Checking fuel supply and tank ventilation systems for leaks

Note. The following describes individual areas in the fuel supply and ventilation systems where leaks are possible. After repairing a possible leak, perform a leak test to ensure that leak was successfully repaired.

1. Switch off ignition.
2. Check whether fuel filler cap of fuel tank was completely sealed for test.
3. Check whether seal of fuel filler cap was damaged or crimped. Replace if necessary.
4. Remove trim for luggage compartment floor.

1. Remove covers for left and right locking flange.

Note. Observe installation notes for locking flanges: Left Installing , right Installing .

1. Check whether seals under locking flanges are OK and lock rings are properly tightened on fuel tank. Also check fuel line connections.
2. Visually check all wires and hose connections of fuel supply system and replace leaking lines, e.g.

1. Line from Evaporative Emission (EVAP) canister to Evaporative Emission (EVAP) Canister Purge Regulator Valve N80 and Evaporative Emission (EVAP) Canister Purge Regulator Valve 2 N333 (in engine compartment)
2. Lines from EVAP canister to Leak Detection Pump (LDP) V144 and to Evaporative Emission (EVAP) Canister Purge Solenoid Valve N115.
3. Line from fuel tank to EVAP canister (below cover for EVAP canister).
4. Fuel lines to engine.

Note. Leaks at lines and components of tank system can sometimes be located using a non-flammable, environmentally compliant leak detection spray. For this, initiate leak diagnostic several times in sequence to build up pressure in the system. At leaking areas, bubbles will form.

1. Perform a visual inspection on fuel system components and tank ventilation system

1. Fuel tank
2. EVAP canister
3. Leak detection pump (LDP) V144
4. Evaporative Emission (EVAP) Canister Purge Solenoid Valve N80

1. Evaporative Emission (EVAP) canister purge solenoid valve N115
2. Evaporative Emission (EVAP) Canister Purge Regulator Valve 2 N333

Note. Due to the form or function of the components, leaking areas may not always be localized by spraying on leak detection spray. It may be necessary to clamp off the relevant component using hose clamps up to dia. 25 mm 3094 and initiate tank leak detection diagnostic. If the leak is no longer indicated, the component that was clamped off is faulty. If clamped off directly at the leak detection pump and a leak is still indicated, the leak detection pump itself is leaking.

Scheme 101

1 - Retaining pin

2 - Bracket for leak detection pump

3 - Vacuum line

1. To front intake pipe

4 - Leak detection pump (LDP) V144

1. Component location: In left rear wheel housing behind wheel housing liner
2. Check using "Guided Fault Finding"
3. Removing and installing --> «Leak Detection Pump (LDP) V144 , removing and installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__leak-detection-pump-ldp-v144)

5 - Angled hose with junction

6 - Angled hose with junction

1. To EVAP canister

7 - Evaporative emission (EVAP) canister purge solenoid valve N115

1. Check using "Guided Fault Finding"
2. Removing and installing --> «Evaporative Emission (EVAP) Canister Purge Solenoid Valve N115 , removing and installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__evaporative-emission-evap-canister-purge-solenoid)

8 - 1.2 Nm

9 - Air filter for diagnosis pump

10 - Hose

11 - Support

1. For Evaporative Emission (EVAP) Canister Purge Solenoid Valve N115

12 - Bracket

1. On body

13 - 9 Nm

Leak Detection Pump (LDP) V144 , removing and installing

Removing

1. Switch off ignition.
2. Remove left rear wheel.
3. Remove left rear wheel housing liner --> «66 - EXTERIOR EQUIPMENT»(/audi/s8/d3-2007-2011/remont/door-locks-anti-theft-systems/#body-exterior) .

Scheme 102

1. Remove hose connectors - 1 - , - 3 - and - 4 -.
2. Disconnect electrical harness connector - 2 - from Evaporative Emission (EVAP) Canister Purge Solenoid Valve N115.
3. Remove bolts - arrows -.
4. Remove Leak Detection Pump (LDP) V144 and disconnect electrical connection.

1. Remove detection pump from bracket.

Installing

1. Tightening torques --> «Leak Detection Pump (LDP) V144 , assembly overview»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system) .

Installation is in reverse order of removal, note the following

Note. Secure all hose connections using hose clamps appropriate for the model type .

1. Install left rear wheel housing liner --> «66 - EXTERIOR EQUIPMENT»(/audi/s8/d3-2007-2011/remont/door-locks-anti-theft-systems/#body-exterior) .

Evaporative Emission (EVAP) Canister Purge Solenoid Valve N115 , removing and installing

Removing

1. Switch off ignition.
2. Remove left rear wheel.

1. Remove left rear wheel housing liner --> «66 - EXTERIOR EQUIPMENT»(/audi/s8/d3-2007-2011/remont/door-locks-anti-theft-systems/#body-exterior) .
2. Separate hose connections - 1 - , - 3 - and - 4 -.
3. Disconnect electrical harness connector - 2 - from Evaporative Emission (EVAP) Canister Purge Solenoid Valve N115.

Scheme 103

1. Remove vacuum hoses - 3 - and - 4 - from Evaporative Emission (EVAP) Canister Purge Solenoid Valve N115 - 2 -.
2. Pull solenoid valve out of mounting - 1 -.

Installing

1. Tightening torque --> «Leak Detection Pump (LDP) V144 , assembly overview»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system) .

Installation is in reverse order of removal, note the following

Note. Secure all hose connections using hose clamps appropriate for the model type .

1. Install left rear wheel housing liner --> «66 - EXTERIOR EQUIPMENT»(/audi/s8/d3-2007-2011/remont/door-locks-anti-theft-systems/#body-exterior) .

Accelerator pedal mechanism, assembly overview

Note. On vehicles with automatic transmissions, a separate Kick Down Switch F8 is installed. Kick down switch F8 , removing and installing --> Kick down switch F8 , removing and installing .

Scheme 104

1 - Accelerator pedal module

1. With Throttle Position (TP) Sensor G79 and Accelerator Pedal Position Sensor 2 G185
2. Removing and installing --> «Accelerator pedal module with Throttle Position (TP) sensors, removing and installing»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__accelerator-pedal-module-with-throttle-position)

2 - 10 Nm

3 - Electrical harness connector

4 - 10 Nm

Accelerator pedal module with Throttle Position (TP) sensors, removing and installing

Removing

1. Remove driver-side storage compartment --> «68 - INTERIOR EQUIPMENT»(/audi/s8/d3-2007-2011/remont/gauges-instrument-panels/#body-interior) .

Scheme 105

1. Separate electrical connector - 2 -.
2. Remove screws - 1 - and - 3 -.
3. Remove accelerator pedal module.

Installing

1. Tightening torque --> «Accelerator pedal mechanism, assembly overview»(/audi/s8/d3-2007-2011/remont/fuel-system/#fuel-supply-system__accelerator-pedal-mechanism-assembly-overview) .

Installation is in reverse order of removal, note the following

1. Install driver-side storage compartment --> «68 - INTERIOR EQUIPMENT»(/audi/s8/d3-2007-2011/remont/gauges-instrument-panels/#body-interior) .

Kick down switch F8 , removing and installing

Removing

1. Pry off covers using a screwdriver.

Scheme 106

1. Remove bolts - arrows - and remove cover for kick-down switch.

Scheme 107

1. Release retaining tab - arrow - with a small screwdriver and turn kick-down switch counter-clockwise.
2. Disconnect electrical harness connector.

Installing

Installation is in reverse order of removal.

See also:
• 24 - MULTIPORT FUEL INJECTION (MFI)
• 27 - BATTERY, STARTER, GENERATOR, CRUISE CONTROL
• 42 - REAR SUSPENSION
• 66 - EXTERIOR EQUIPMENT
• 26 - EXHAUST SYSTEM, EMISSION CONTROLS
• 68 - INTERIOR EQUIPMENT
• Fuel tank, emptying
• Installed location of spacer
• Fuel tank with attachments, removing and installing
• Installing
• Installed location of right locking flange
• Fuel Level Sensor G , checking (left lever-type sensor)
• Fuel Level Sensor G (left lever-type sensor), removing and installing
• Left fuel delivery unit with Transfer Fuel Pump (FP) G6 , removing and installing
• Fuel Level Sensor 3 G237 , checking (left tubular sensor)
• Fuel Level Sensor 3 G237 (left tubular sensor), removing and installing
• Checking voltage supply
• Fuel Level Sensor 2 G169 , checking (right lever sensor)
• Fuel Level Sensor 2 G169 (right lever sensor), removing and installing
• Fuel Level Sensor 4 G393 (right tubular sensor), checking
• Fuel Pump (FP) G23 (right), checking electrical
• Right fuel delivery unit with Fuel Pump (FP) G23 , removing and installing
• Fuel filter for vehicles without auxiliary heater, removing and installing
• Fuel filter for vehicles with auxiliary heater, removing and installing
• Fuel filter for vehicles without fuel system return line, removing and installing
• Diagnostic leak test, performing
• Checking fuel supply and tank ventilation systems for leaks
• Leak Detection Pump (LDP) V144 , removing and installing
• Evaporative Emission (EVAP) Canister Purge Solenoid Valve N115 , removing and installing
• Kick down switch F8 , removing and installing
• Accelerator pedal module with Throttle Position (TP) sensors, removing and installing
• Accelerator pedal mechanism, assembly overview