High Pressure Pump Overview

High Pressure Pump Overview


The fuel system is under pressure!

• Before opening high pressure components of the fuel injection system, the fuel pressure must be relieved to residual pressure, refer to => [ High Side Fuel Pressure, Releasing ] Service and Repair.






1 Cam Follower

• Remains inserted in the cylinder head after removing the high pressure pump, removable.

2 O-ring

• Always replace

3 High Pressure Pump

• An electrical fuel pump, located in the fuel tank, supplies fuel to the mechanical high pressure pump at a pressure of approximately 7 bar.

• When installing the high pressure pump, make sure that no dirt enters the fuel system.

• The fuel system must be pressureless to install the high pressure pump, releasing fuel pressure, refer to => [ High Side Fuel Pressure, Releasing ] Service and Repair.

• Install the fuel line to the fuel rail free of tension.

• Removing and installing, refer to => [ High Pressure Pump ] High Pressure Pump.

4 Fuel Pressure Regulator Valve (N276)

5 Bore in the Cylinder Head

• For the high pressure pump.

6 Fuel Injector

• Cylinder 1 fuel injector (N30).

• Cylinder 2 fuel injector (N31).

• Cylinder 3 fuel injector (N32).

• Cylinder 4 fuel injector (N33).

• With the combustion chamber seal (Teflon seal), always replace; refer to => [ Fuel Injector Teflon Seal ] Fuel Injector Teflon Seal.

• Replace the O-rings.

• Note the correct installed position.

• Removing and installing, refer to => [ Fuel Injector ] Fuel Injector.

• Cleaning, refer to => [ Fuel Injector, Cleaning ] Service Precautions.

7 Camshaft Position Sensor (G40)

• Bolted on the front of the cylinder head cover. Refer to => [ Camshaft Position (CMP) Sensor ] Service and Repair.

8 Camshaft Adjustment Valve 1 (N205)

• Removing and installing, refer to => [ ] Service and Repair.

9 Bolts

• M6 threads: 8 Nm + 90° (1/4) additional turn. Replace.

• M8 threads: 20 Nm.

10 Connecting Piece

• For the fuel supply line.

• From the fuel tank.

11 Connecting Piece

• 22 Nm

• Always replace.

• For the high pressure fuel line to the fuel rail.