Schematic Overview - Fuel System
Danger of malfunction caused by dirt.
- Follow the rules for clean working conditions. Refer to CLEAN WORKING CONDITIONS .
Follow the points below to avoid running the high pressure fuel pump dry and to start the engine quickly after replacing the components:
- If fuel system components between the fuel tank and high pressure fuel pump are removed or replaced, then a fuel first filling must be performed.
- It is necessary to bleed the fuel system before starting the engine for the first time if the fuel pump, the fuel line (between the fuel tank and the high pressure fuel pump) or the fuel filter were removed.
- If the high pressure fuel pump was removed or replaced, then bleed the fuel system before starting the engine for the first time.
Filling the fuel for the first time. Refer to FUEL SYSTEM, FILLING/BLEEDING .
If these instructions are not followed, the high pressure pump will be damaged during the first filling.
- Fuel Metering Valve -N290-
- Do not open
- High Pressure Pump
- Perform an adaptation after replacing the high pressure pump and / or the Fuel Pressure Regulator Valve -N276- on the Vehicle Diagnostic Tester.
- Overview. Refer to OVERVIEW - HIGH PRESSURE PUMP .
- Removing and installing. Refer to HIGH PRESSURE PUMP, REMOVING AND INSTALLING .
- High Pressure Reservoir (Rail)
- For cylinder bank 1 (right)
- Fuel Pressure Regulator Valve -N276-
- Always replace if removed
- Perform an adaptation after replacing the high pressure pump and / or the Fuel Pressure Regulator Valve -N276- on the Vehicle Diagnostic Tester.
- Removing and Installing. Refer to Fuel Pressure Regulator Valve -N276-, REMOVING AND INSTALLING .
- Tightening specification. Refer to Fig 1.
- Fuel Pressure Sensor -G247-
- Reuse is possible Installing - The Fuel Pressure Sensor -G247- has a biting edge instead of a sealing ring.
- Removing and installing. Refer to Fuel Pressure Sensor -G247-, REMOVING AND INSTALLING .
- Tightening specification. Refer to Fig 2.
- High Pressure Reservoir (Rail)
- For cylinder bank 2 (left)
- Injector
- Removing and installing. Refer to FUEL INJECTORS, REMOVING AND INSTALLING .
- Fuel Supply Hose
- Do not disassemble
- Restrictor
- There is very little remaining pressure in the fuel supply hoses
- Not able to be replaced separately; replace the fuel supply hoses if they are faulty
- Transfer Fuel Pump -G6-
- Fuel Filter
Fuel Pressure Regulator Valve N276 - Tightening Specification
-- Align the Fuel Pressure Regulator Valve -N276- so that connecting the connector -arrow- does not cause the electrical wiring to be placed under tension.
-- Tighten the union nut on the regulator valve in 4 steps as follows. Counterhold it by the housing.
| Step | Tightening Specification |
|---|---|
| 1. | Install all the way in by hand. |
| 2. | 60 Nm |
| 3. | Turn back 180° |
| 4. | 85 Nm |
Fuel Pressure Sensor G247 - Tightening Specification
-- Tighten the Fuel Pressure Sensor -G247- in four steps as follows:
Do not use an open-end wrench for opening or tightening.
Reuse of the Fuel Pressure Sensor -G247- is possible. Refer to Installing - The Fuel Pressure Sensor -G247- has a biting edge instead of a sealing ring. .
Special tools and workshop equipment required
- Socket - 27mm: T40218
- Torque wrench
| Step | Tightening Specification |
|---|---|
| 1. | Install all the way in by hand. |
| 2. | 60 Nm |
| 3. | Turn back 180° |
| 4. | 85 Nm |