FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Fuel Rail, Injectors and High Pressure Pump Overview






Fuel Rail, Injectors and High Pressure Pump Overview

Do not disassemble the high pressure pump!

If a fuel injector is removed, then the combustion chamber Teflon seal and washer must always be replaced. Refer to => [ Fuel Injector Teflon(R) Seal and Washer ] Fuel Injector Teflon(R) Seal and Washer.

Read the safety precautions before starting. Refer to => [ Safety Precautions ] Fuel Supply.

Pay attention to the rules of cleanliness. Refer to => [ Clean Working Conditions ] Multiport Fuel Injection.

If the battery is not going to be disconnected, then remove the fuel pump fuse. Otherwise the door contact switch inside the driver's door could activate the fuel pump.

Fuel pressure in the high pressure pipe can be up to 120 bar! Always wear protective eye wear and protective clothing to prevent injuries and fuel from coming in contact with your skin. Before loosening the fuel pipe, place a cloth around the connection point. Then release pressure by carefully loosening the union nuts.






1 Bolt

30 Nm + an additional 90° (1/4) turn.

Always replace.

Tighten uniformly, starting from the inside and working toward the outside.

2 Fuel Rail

For cylinders 1, 3 and 5.

Always replace the fuel injector springs - items 11 and 23 - before installing.

Tighten the bolts uniformly, starting from the inside and working toward the outside.

To remove, remove the lower intake manifold. Refer to => [ Lower Intake Manifold, with Fuel Rail ] Lower Intake Manifold, with Fuel Rail.

3 Spring Clamp

4 Low Fuel Pressure Sensor (G410)

15 Nm

5 Fuel Supply Hose

From the fuel tank.

With a mount for the low fuel pressure sensor.

Always replace the supply hose because it is damaged when it is removed from the ridged connections.

6 Bolt

8 Nm

7 Bolt

8 Nm

8 Bracket

For the fuel hose.

9 O-ring

Always replace.

Before installing, lubricate with clean engine oil.

10 Washer

Replace if damaged. Refer to => [ Fuel Injector Teflon(R) Seal and Washer ] Fuel Injector Teflon(R) Seal and Washer.

11 Spring

Replace every time the fuel rail is removed.

Make sure it is secure.

12 Cylinder 1 Fuel Injector (N30)

Cylinder 3 fuel injector (N32)

Cylinder 5 fuel injector (N83)

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

The long fuel injectors for cylinders 1, 3 and 5 must not be separated.

13 Seal

Always replace.

Before installing, lubricate with clean engine oil.

14 Low Pressure Fuel Hose

Between the high pressure pump and fuel rail.

Always replace the fuel hose because it is damaged when it is removed from the ridged connections.

15 Spring Clamp

16 High Pressure Fuel Pipe

28 Nm

Place a clean cloth around the connection before disconnecting. Then release pressure by carefully loosening the union nuts.

The fuel pipe must not touch other components!

To loosen and tighten the union nuts, counter hold the connection on the high pressure pump using a wrench.

Before installing: First, tighten the connection on the high pressure pump to 40 Nm.

Loosen and tighten the union nuts using the flare nut attachment 17 mm (T10456)

Do not install when under tension.

To install, first tighten the union nuts by hand.

17 Connecting Pipe

28 Nm

The pipe must not touch other components!

Do not install when under tension.

To install, first tighten the union nuts by hand.

Before installing: First, tighten the connection on the high pressure pump to 40 Nm.

18 Cam Follower

Lubricate the O-rings with clean engine oil before installing.

19 O-ring

Always replace.

Before installing, lubricate with clean engine oil.

20 High Pressure Pump

With the fuel pressure regulator valve.

To loosen and tighten the fuel lines, counter hold the connection using a wrench.

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

Before installing the fuel lines, first, tighten the connection for the fuel lines:

Connection for the high pressure line: 40 Nm

Connection for the low pressure line: 28 Nm

21 Bolt

10 Nm

22 Cylinder 2 Fuel Injector (N31)

Cylinder 4 fuel injector (N33)

Cylinder 6 fuel injector (N84)

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

23 Spring

Replace every time the fuel rail is removed.

Make sure it is secure.

24 Washer

Replace if damaged. Refer to => [ Fuel Injector Teflon(R) Seal and Washer ] Fuel Injector Teflon(R) Seal and Washer.

25 O-ring

Always replace.

Before installing, lubricate with clean engine oil.

26 Fuel Rail

For cylinders 2, 4 and 6.

Replace the springs - item 23 - before installing.

Tighten the bolts uniformly, starting from the inside and working toward the outside.

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

27 Bolt

30 Nm + an additional 90° (1/4) turn.

Always replace.

Tighten uniformly, starting from the inside and working toward the outside.

28 Fuel Pressure Sensor (G247)

22 Nm

Before installing, coat the front sealing point and threads with clean engine oil.

29 Plug

22 Nm

30 Pressure Relief Valve

Lightly coat the O-rings with clean engine oil before installing.

Replace the removed valve.

Press in by hand using a 8 mm hex wrench.

31 O-ring

Always replace.

Before installing, lubricate with clean engine oil.