AutoZone 1991 Land Rover Range Rover 3.9L MFI 8cyl | Repair Guides | Fuel System | Fuel Lines And Fittings | Fuel Injector(s) | AutoZone.com

Search suggestions

    My Vehicles

    1991 Land Rover Range Rover 3.9L MFI 8cyl

    My Store

    405 N COLLEGE ST
    (479) 443-4043

    CLOSED Open at 7:30 AM

    SAVE 20% + GET A $10 GIFT CARD ON ONLINE SHIP-TO-HOME ORDERS OVER $100.

    Use Code: LABORDAY

    See Details

    VW Passat & Audi A4 1990-2000

    Fuel Injector(s)

    Print

    REMOVAL & INSTALLATION
    1990-93 VW Passat

    The fuel injectors are not timed, nor are they switched on and off electrically. The mechanical fuel injectors are actually not injectors at all. They are precise nozzles that, above a certain minimum fuel pressure, discharge and atomize fuel.


    CAUTION
    Observe all applicable safety precautions when working around fuel. Whenever servicing the fuel system, always work in a well-ventilated area. Do NOT allow fuel spray or vapors to come in contact with a spark or open flame. Keep a dry chemical fire extinguisher near the work area. Always keep fuel in a container specifically designed for fuel storage; also, always properly seal fuel containers to avoid the possibility of fire or explosion.


    NOTE
    The fuel injectors are mounted in 2-piece inserts that thread into the intake manifold runners. Flexible O-rings provide a seal and hold the injectors in place

    1. Relieve the fuel system pressure. See "Relieving Fuel System Pressure."
    2.  
    3. On CIS-E Motronic systems pull the injectors straight out of inserts, using a tool designed specifically for the job. Fuel injector removal tools are sold at most automotive suppliers or at your local VW dealer.
    4.  


    NOTE
    The O-rings provide a good seal, and some force is required to remove the injectors. Pull or pry only on the injectors themselves, not on the fuel lines,

    1. Now, hold the fitting with a line wrench and unscrew the injector from the fuel line.
    2.  


    NOTE
    If it is difficult to remove the injectors from their lines, use a penetrant to aid in the process.

    1. The injectors can now be removed from the lines if desired.
    2.  


    NOTE
    The larger sealing O-ring may not come out with the injector. If this happens, carefully remove the large O-ring from the injector bore. Replace the O-ring onto the injector during installation. This will help avoid pushing it into the engine as you reinstall the injector.

    To install:

    1. Installation is the reverse of the removal procedure.
    2.  
    3. Install the fuel injectors on the lines using proper line wrenches.
    4.  
    5. Lubricate the injector O-rings with gasoline for several minutes before installing them.
    6.  


    NOTE
    The thick rubber O-ring should always be replaced. Make sure the O-ring is fully seated in the groove.

    1. Install the injectors.
    2.  



    Click image to see an enlarged view

    Fig. Typical fuel injector and inserts that mount in the intake manifold.


    NOTE
    The injector inserts Do NOT normally require attention, except to make sure that they seal well and Do NOT allow air leaks.

    1994-97 VW Passat 2.0L
    1. Turn ignition switch to OFF and remove the keys
    2.  
    3. Release the fuel system pressure. See "Relieving Fuel System Pressure"
    4.  
    5. Remove upper intake manifold. See Engine, Intake Manifold, Upper
    6.  
    7. Remove fuel rail and injectors
    8.  

    To Install:

    1. Installation is the reverse of the removal procedure. Note the following:
    2.  
      1. Always replace the gasket (below the lower insert) before the fuel injectors are installed.
      2.  
      3. Before the upper insert is installed, clean the threads and apply a light coat of threadlock compound.
      4.  


    1994-97 VW Passat 2.8L

    NOTE
    Removal of the injectors requires removal of the upper intake manifold and fuel rail, as included in the following procedure. For complete procedure on upper intake manifold, see Engines, Intake Manifold, Upper.

    1. Turn ignition switch to OFF and remove the keys
    2.  
    3. Release the fuel system pressure. See "Relieving Fuel System Pressure"
    4.  
    5. Remove or disconnect the following:
    6.  
    7. Ignition wires
    8.  
    9. Hose from mass airflow sensor
    10.  
    11. Hose from fuel EVAP solenoid (at throttle body)
    12.  
    13. TP sensor
    14.  
    15. IAC valve
    16.  
    17. Accelerator cable from throttle body
    18.  
    19. Air intake heated tube hose
    20.  
    21. Fuel lines from fuel rail
    22.  
    23. Fuel pressure regulator vacuum hose
    24.  
    25. Upper intake manifold
    26.  
    27. Fuel rail, with injectors
    28.  
    29. Wiring harness from fuel injectors
    30.  
    31. Clips from injectors
    32.  


    NOTE
    If the fuel injectors are seated too tightly in the lower intake manifold, carefully pry them out, using a 16mm wrench under the Fuel Injector body.

    To install:

    1. To install, reverse removal procedure. Always use new O-rings on injectors and lubricate the O-rings prior to installation.
    2.  

    1998-2000 Passat & 1996-2000 Audi A-4 1.8L, 2.0L
    1. Turn the ignition switch OFF and remove the keys
    2.  
    3. Release the fuel system pressure. See "Relieving Fuel System Pressure"
    4.  
    5. Remove or disconnect the following:
    6.  
    7. Fuel lines from the fuel injector rail
    8.  
    9. Fuel rail bolts
    10.  
    11. Fuel rail, with injectors
    12.  

    To install

    1. Installation is the reverse order of the removal procedure. Note the following:
    2.  
      1. Always replace the gasket (below the lower insert) before the fuel injectors are installed.
      2.  
      3. Before the upper insert is installed, clean the threads and apply a light coat of thread-lock compound.
      4.  


    1998-2000 VW Passat & 1996-2000 Audi A-4 2.8L (V6 & VR6)
    1. Remove the engine cover
    2.  
    3. Remove the air intake hose between the mass airflow sensor and intake air elbow
    4.  
    5. Remove all harness connectors to injectors
    6.  
    7. Disconnect vacuum hose from fuel pressure regulator
    8.  
    9. Expose wires at fuel rail
    10.  



    Click image to see an enlarged view

    Fig. Removing the fuel injector rail

    1. Unscrew fuel rail from intake manifold (arrows)
    2.  


    WARNING
    Fuel system is under pressure! Place a cloth around the connection point before opening the system. Then release pressure by carefully loosening connection.

    1. Disengage retaining clip and remove the injector
    2.  

    To install

    1. Installation is in reverse order of removal, noting the following:
    2.  
      1. Remove the O-rings from all opened connections. NEVER remove the plastic cap from valve head to replace front O-ring; pry the O-ring off over the plastic cap.
      2.  
      3. Lightly lubricate the O-ring with clean engine oil.
      4.  
      5. Make sure all the injectors are in place and seated correctly.
      6.  
      7. Check the clip to ensure an unobstructed fitting on injector.
      8.  
      9. Place the fuel rail with injectors into the intake manifold, and apply uniform pressure to press it in.
      10.  


    TESTING
    1990-93 VW Passat
    Injector Output

    CAUTION
    During the following test procedures fuel will be discharged from all 4 injectors. Do NOT perform these tests near fire hazards. Keep test times as short as possible. Keep plenty of shop rags and clean containers handy to catch expelled fuel.


    CAUTION
    All injectors should be removed from their inserts when testing. Fuel discharged by injectors that remain installed can flood the engine and permanently damage the catalytic converter.


    NOTE
    Sensor plate clearance should be checked prior to performing the following tests.

    1. Remove all injectors from their inserts. Leave the injectors attached to the fuel lines.
    2.  
    3. Bypass the fuel pump relay.
    4.  
    5. Using a magnetic tool, lift the airflow sensor plate slowly and evenly.
    6.  


    CAUTION
    Prepare to catch discharged fuel in a suitable container.

    1. Check the spray pattern of each injector. Fuel should discharge in an even, cone-shaped pattern of very fine droplets. If not raise the airflow sensor plate completely and check again.
    2.  
    3. Release the airflow sensor plate.
    4.  
    5. The flow from the injectors should stop. Hold the injector in a horizontal position and verify that there are no drips from the injector tips.
    6.  


    NOTE
    Checking injector fuel delivery requires special diagnostic equipment. It is recommended to have this procedure done by a repair facility with required special equipment.

    1994-2000 Passat 1.8L, 2.0L, 2.8L (V6 & VR6); 1996-2000 Audi A4 2.8L
    Fuel Injector Electrical Diagnosis and Activation

    WARNING
    Fire hazard! Do NOT smoke or work near heaters or open flame. Do NOT have anything nearby that could ignite fuel. The fuel system is under pressure. Before opening, cover connections with a rag, and open carefully to release pressure.

    1. Obtain the following special tools and equipment:
    2.  
    3. VAG 1551 or VAG 1552 scan tool, with VAG 1551/3 adapter cable
    4.  
    5. Audi A4, VW 1594 test kit
    6.  
    7. VAG 1598/22 test box
    8.  
    9. Multimeter US1119 (Fluke 83, or equivalent)
    10.  
    11. VAG 1348/3A remote control, with adapter cable VAG1348/32
    12.  
    13. VAG 1527B LED voltage tester
    14.  
    15. VAG 1602 measuring glass from calibration tester
    16.  
    17. Wiring diagram for the specific vehicle and engine being tested
    18.  
    19. Verify that the engine speed sensor and fuel pump are operational.
    20.  
    21. Remove all components necessary for access to the fuel injectors.
    22.  
    23. Using the scan tool, run the "Diagnostic Test" mode for actuating the fuel injectors.
    24.  
    25. If one or more injectors Do NOT click, perform the following tests:
    26.  
      1. Disconnect the 5-pin harness connector from ignition coil.
      2.  
      3. Disconnect the harness connectors (1) from all injectors (2).
      4.  
      5. Connect the VAG 1527B LED voltage connector terminals for cylinder/fuel injector, using the adapter cables from VW1594 connector test kit.
      6.  
      7. Operate the starter and check voltage supply for cylinder No. 1 fuel injector.
      8.  
      9. The LED must flicker.
      10.  
      11. Repeat the test for all remaining injectors.
      12.  
      13. Turn the ignition switch off.
      14.  
      15. Connect the VAG1527B LED voltage tester to cylinder No. 1 harness connector terminal No. 1 and ground.
      16.  
      17. Operate the starter.
      18.  
      19. The LED must light.
      20.  
      21. If the LED does not light, switch the ignition OFF and check the wire between the 2-pin connector terminal No. 1 and the fuel pump relay for an open circuit. The specified value is 1.5 ohms (maximum).
      22.  
      23. Connect the VAG 1598/22 test box to ECM harness connector.
      24.  
      25. Check the wiring for open circuits between the ECM/test box and each fuel injector.
      26.  
      27. Check the wiring for short circuits between all circuit wires and connector terminals.
      28.  
      29. Check the wiring between connector terminal No. 1 of all injectors and ground for open circuit.
      30.  




    Click image to see an enlarged view

    Fig. Disconnecting the harness from all injectors



    Click image to see an enlarged view

    Fig. Checking for a proper ground, using VAG 1527B tester



    Click image to see an enlarged view

    Fig. Connecting the test box VAG1598/22 to the ECM harness

    1. To check for fuel injector resistance perform the following:
    2.  
      1. Remove the harness connector from each injector.
      2.  
      3. With a DVOM, check the resistance at each fuel injector. Specified resistance is 13.5-15.5 ohms.
      4.  
      5. If the injector is not within specification, replace the injector.
      6.  


    Fuel Injector Leak Test

    NOTE
    Verify proper operation of the fuel pressure regulator prior to performing these tests.

    1. Remove all components necessary in order to remove the fuel rail and attached injectors.
    2.  
    3. Remove the injector rail and injectors as an assembly. Support this assembly out of the way above the manifold.
    4.  


    NOTE
    Leave the injector harness attached to injectors.

    1. Conduct an output Diagnostic Test Mode (DTM), actuating the No. 1 cylinder fuel injector. The fuel pump must be running.
    2.  


    NOTE
    This step allows the fuel pump to run without the engine running. The closed throttle position switch must be closed during the test, or the selected injector will be activated 5 times, discharging fuel.

    1. Visually check fuel injector for leaks. A maximum of 1 to 2 drops per minute per injector.
    2.  
    3. If leak exceeds allowed amount, switch the ignition key OFF and replace the injector.
    4.  


    NOTE
    Always replace the seals.

     
    AutoZone Logo