Fuel Injectors Overview

Fig 1: Exploded View Of Fuel Injectors

Courtesy of AUDI OF AMERICA, LLC

1. Counter Pin
   • For the tensioning claw
   • Various tightening specifications:
     • 2.5 Nm on camshaft bearing
     • 9 Nm on cylinder head
2. Tensioning Claw
   • Mark the part allocations for reinstallation and follow them when installing
   • The tensioning claw and fuel injector belong together
   • When exchanging (as a test), the tension clamp moves with the fuel injector
   • After troubleshooting, the tensioning claw and the fuel injector are reinstalled on the original cylinder
   • When replacing a fuel injector, the tensioning claw must also be replaced
3. Bolt
   • Replace
   • First tightening 8 Nm
   • Second tightening 90 degrees
4. High Pressure Line
   • 25 Nm
   • From high pressure pump to fuel rail
   • Do not change the shape of the line
   • Check for damage before installing
   • Installing, refer to HIGH PRESSURE LINES, INSTALLING 
   • Coat the union nut threads with clean engine oil
5. Clamp
   • For high pressure line
6. Bolt
   • 9 Nm
7. Clamp
   • For high pressure line
8. Bolt
   • 9 Nm
9. High Pressure Line
   • 25 Nm
   • From the opposite fuel rail
   • Do not change the shape of the line
   • Check for damage before installing
   • Installing, refer to HIGH PRESSURE LINES, INSTALLING 
   • Coat the union nut threads with clean engine oil
10. Fuel Rail
    • Removing and installing. Refer to FUEL RAIL .
11. Fuel Return Hose
    • To fuel tank
12. Fuel Return Hose
    • From fuel injectors
    • Do not disassemble
    • Replace completely along with the restrictor
    • After replacing the engine, allow engine to idle for 2 minutes to bleed the fuel system.
    • Then, check the fuel supply hoses for leaks
13. Hose Connection Ring
14. Banjo Bolt
    • 25 Nm
15. Seals
    • Replace
16. Fuel Pressure Regulator Valve -N276-
    • With biting edge for sealing
    • Cannot be used again
    • Perform an adaptation after replacing the high pressure pump and / or the Fuel Pressure Regulator Valve -N276-. Use a vehicle diagnosis tester
    • Removing and installing, refer to Fuel Pressure Regulator Valve -N276- 
    • Tightening specification, refer to Fig 2
17. Bolt
    • 22 Nm
18. High Pressure Line
    • 25 Nm
    • From fuel rail to fuel injector
    • Do not change the shape of the line
    • Mark the part allocations for reinstallation and follow them when installing
    • Check for damage before installing
    • Installing, refer to HIGH PRESSURE LINES, INSTALLING .
    • Coat the union nut threads with clean engine oil
19. Fuel Return Hose
    • From fuel injectors
    • Do not disassemble
    • Replace completely along with the restrictor
    • After replacing the engine, allow engine to idle for 2 minutes to bleed the fuel system.
    • Then, check the fuel supply hoses for leaks
20. O-ring
    • Replace
21. Injector
    • Mark the part allocations for reinstallation and follow them when installing
    • The fuel injector and tension clamp belong together
    • When exchanging (as a test), the tensioning claw moves with the fuel injector
    • Replace the copper ring seal during every assembly/disassembly procedure.
    • After troubleshooting (exchange), the fuel injector and tensioning claw are reinstalled on the original cylinder.
    • To remove rust particles on the fuel injector sealing surface, clean the fuel injector shaft in the cylinder head using the Cleaning SetVAS 6811 (always clean in the event of leaks).
    • When replacing a fuel injector, the tensioning claw must also be replaced
    • Removing and installing, refer to FUEL INJECTORS .
22. O-ring
    • Replace
23. Copper Sealing Ring
    • Replace the copper ring seal during every assembly/disassembly procedure.

Fig 2: Fuel Pressure Regulator Valve -N276-

Courtesy of AUDI OF AMERICA, LLC

-- Align the fuel pressure regulator valve -N276- such that connecting the harness connector -arrow- does not cause the electrical wiring to be placed under tension.

-- Counterhold the housing hex bolt to tighten union nut on regulator valve in 4 stages as follows:

Fig 3: Fuel Pressure Sensor -G247- - Tightening Specification

Courtesy of AUDI OF AMERICA, LLC

-- Tighten fuel pressure sensor -- in 4 steps as described below:

Special tools and workshop equipment required 

• Socket 27 mmT40218
• Torque wrench