System Overview

System Overview


• Follow the safety precautions when working on the diesel direct injection system. Refer to => [ Safety Precautions ] Diesel Fuel Injection.

• Observe the rules for cleanliness => [ Clean Working Conditions ] Diesel Fuel Injection.

• If fuel system components between the fuel tank and high pressure fuel pump were removed or replaced, the fuel system must be filled in order to bleed it. Refer to => [ Fuel System, Filling and Bleeding ] Fuel System, Filling and Bleeding. (Never let the high pressure pump run dry).

Always follow these instructions before and during work.






1 Fuel Metering Valve (N290)

• Do not open

2 High Pressure Fuel Pump

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

• The fuel system "must" always be filled after replacing (never run dry). Refer to => [ Fuel System, Filling and Bleeding ] Fuel System, Filling and Bleeding.

3 Fuel Pressure Sensor (G247)

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

4 Fuel Rail

5 Fuel Pressure Regulator Valve (N276)

• 80 Nm

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

6 Fuel Injector

• Cylinder 1 fuel injector (N30)

• Cylinder 2 fuel injector (N31)

• Cylinder 3 fuel injector (N32)

• Cylinder 4 fuel injector (N33)

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

7 Fuel Return Lines

• The fuel return line must be routed correctly. They may be replaced only with the pressure retaining valve.

• Run the engine at idle for approximately two minutes after replacing to bleed the fuel system and then check the fuel return lines for leaks.

8 Pressure Retention Valve

• The valve always maintains a residual pressure (control quantity) of approximately 10 bar in the fuel return lines.

• The fuel injectors require this control quantity to function correctly.

• The pressure retention valve must be replaced completely with the fuel return lines - item 7 -.

• The engine must run at idle for approximately two minutes after replacing to bleed the fuel system.

• Pressure retention valve in fuel return line, checking. Refer to => [ Pressure Retention Valve in Fuel Return Line, Checking ] Testing and Inspection.

9 Fuel Tank

• Assembly overview, refer to one of the following:

• Jetta from MY 05 through 10, Jetta SportWagen (US)/Jetta Wagon (Canada) for MY 09 and Jetta SportWagen (US)/Golf Wagon (Canada) from MY 10, refer to => [ Fuel Tank Overview ] Fuel Tank Overview.

10 Fuel Filter

• Assembly overview, refer to => [ Fuel Filter Overview ] Fuel Filter Overview.

11 Auxiliary Fuel Pump (V393)

• Removing and installing, refer to => [ (In-Line Electric Fuel Pump) ] Auxiliary Fuel Pump (V393) (In-Line Electric Fuel Pump).