FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
Courtesy of Operation CHARM: Car repair manuals for everyone.

Fuel Rail Overview






Fuel Rail Overview






1 Fuel Injector

With combustion chamber seal (Teflon seal), always replace.

Replace O-rings

Note the correct installed position.

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

2 Support Ring

3 Fuel Rail

Removing and installing, refer to => [ Fuel Rail, Separating from the Intake Manifold ] Intake Manifold With Fuel Rail.

4 High Pressure Pump

With the fuel pressure regulator valve.

An electrical fuel pump located in the fuel tank supplies fuel to the mechanical high pressure pump at a pressure of approximately 6 bar.

Make sure dirt does not enter the fuel system when installing the high pressure pump.

The fuel system must be pressureless to install the high pressure pump, releasing fuel pressure, refer to => [ Safety Precautions ] Fuel Supply.

Do not install fuel lines under tension.

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

5 Roller Tappet

6 Fuel Pressure Regulator Valve (N276)

7 Bolt

M6 threads = 10 Nm

M8 threads = 20 Nm

Always replace

8 Fuel Supply Line Connection

22 Nm

Always replace

9 Fuel Supply Line Union Nut

18 Nm

10 Channel Separating Plates

11 Gasket

Always replace

12 Intake Manifold

Removing and installing, refer to => [ Intake Manifold with Fuel Rail ] Intake Manifold With Fuel Rail.

13 Vacuum Diaphragm for the Channel Separating Plate

Checking, refer to => [ Variable Intake Manifold, Checking ] Testing and Inspection.

14 Throttle Valve Control Module (J338), Electronic Power Control (EPC) Throttle Drive (G186)

EPC throttle drive angle sensor 1 (G187) and EPC throttle drive angle sensor 2 (G188).

After replacing the throttle valve control module, it must be readapted to the Engine Control Module (ECM). Refer to "Guided Functions" in the vehicle diagnostic tester.

15 Bolt

Tighten to 3 Nm, and then tighten to 9 Nm.

16 Intake Manifold Runner Position Sensor (G336)

To remove and install, remove the intake manifold. Refer to => [ Intake Manifold with Fuel Rail ] Intake Manifold With Fuel Rail.

17 Fuel Pressure Sensor (G247)

27 Nm

Lubricate the threads with clean engine oil.

Checking, refer to => [ , Checking ] Fuel Pressure Sensor (G247), Checking.

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

Additional Tightening Specifications

Additional tightening specifications can be found at the end of the "Fuel Rail, Separating from Intake Manifold". Refer to => [ Fuel Rail, Separating from the Intake Manifold ] Intake Manifold With Fuel Rail.