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Home >> Buick >> 2021 >> Envision Preferred, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls And Fuel - 2.0L (LSY) - Repair Instructions >> Repair Instructions >> Fuel Injection Fuel Rail Assembly Replacement >> Installation Procedure
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Installation Procedure

  1. Fig 1: Identifying Fuel Injector Seals And Replacement Components
    GM4840511Courtesy of GENERAL MOTORS COMPANY
    NOTE:

    DO NOT use any type of lubricant when installing the NEW combustion seals on the fuel injector tip.

    Install EN-51955-1  Long Protector (1) onto the fuel injector tip, covering the first recessed area closest to the tip. Place a NEW fuel injector nozzle housing seal (2) on EN-51955-1  Long Protector (1).

  2. Using EN-51955-4  Pusher (3), install the fuel injector nozzle housing seal (2) into the recessed area (4) of the fuel injector, then remove the EN-51955-1  Long Protector.
  3. Compress the fuel injector nozzle housing seal (2) using EN-51955-3  Pre-Sizer (5).
  4. Using EN-51955-5  Sizer (6), resize the fuel injector nozzle housing seal.
  5. Install EN-51955-2  Short Protector (7) onto the fuel injector tip. Place a second NEW fuel injector nozzle housing seal (8) on EN-51955-2  Short Protector (7).
  6. Using EN-51955-4  Pusher (3), install the fuel injector nozzle housing seal (8) into the remaining recessed area (9) of the fuel injector, then remove EN-51955-2  Short Protector.
  7. Compress the fuel injector nozzle housing seal (8) using EN-51955-3  Pre-Sizer (5).
  8. Using EN-51955-5  Sizer (6), resize the fuel injector nozzle housing seal.
  9. GM2918356Courtesy of GENERAL MOTORS COMPANY
    NOTE:

    The fuel injector nozzle housing seals must fit properly in the relative groove. Overlapping of the fuel injector nozzle housing seals with the external surface of the injector must be avoided.

    Check both of the fuel injector nozzle housing seals on each fuel injector for correct seat:

    • The fuel injector nozzle housing seal must not be too large, buckled, or corrugated (1)
    • The fuel injector nozzle housing seal must be fixed tight and accurate (2)
  10. If the fuel injector nozzle housing seals are not installed correctly, remove the incorrect fuel injector nozzle housing seal and replace with a NEW fuel injector nozzle housing seal.
  11. GM4995644Courtesy of GENERAL MOTORS COMPANY
    NOTE:

    Hand place the fuel injection fuel rail into the position on the cylinder head.

    Fuel Injection Fuel Rail (1) - Install

  12. Fig 2: Identifying Fuel Injection Fuel Rail, Bolts And Electrical Connectors
    GM4995756Courtesy of GENERAL MOTORS COMPANY
    NOTE:

    Install the 4 fuel injection fuel rail bolts with zero torque.

    Fuel Injection Fuel Rail Bolt (1, 2, 3) - Install [4x]

  13. Tighten the 2 outer fuel injection fuel rail bolt (1, 3) alternating in steps of 1/2 turn, until the fuel injection fuel rail (4) is fully seated.
    14. CAUTION:

    Refer to Fastener Caution .

  14. Fuel Injection Fuel Rail Bolt (1, 2, 3) - Tighten [4x] 36 N.m (27 lb ft)
  15. Electrical Connector (5, 6) - Connect [2x]
  16. GM4995197Courtesy of GENERAL MOTORS COMPANY
    WARNING:

    The noise cancelling foam component MUST be replaced if it has been exposed to engine fluids. Failure to replace the noise cancelling foam component that has been exposed to engine fluids may result in an engine fire resulting in catastrophic engine damage, and possible injury or death.

    Fuel Injection Fuel Rail Insulator (1) - Install

  17. Wiring Harness (2) @ Fuel Injection Fuel Rail Insulator (1) - Install
  18. Fuel Feed Intermediate Pipe - Install Fuel Feed Intermediate Pipe Replacement 
  19. GM5065029Courtesy of GENERAL MOTORS COMPANY

    Engine Coolant Flow Control Valve (1) - Install Engine Coolant Flow Control Valve Replacement

  20. Install the intake manifold and throttle body together as an assembly. Intake Manifold Replacement
  21. Charge Air Cooler Outlet Air Hose - Install Charge Air Cooler Outlet Air Hose Replacement 
  22. Connect the battery negative cable. Battery Negative Cable Disconnection and Connection
  23. Inspect for fuel leaks using the following procedure:
    1. Turn ON the ignition with the engine OFF for 2 seconds.
    2. Turn OFF the ignition for 10 seconds.
    3. Turn ON the ignition with the engine OFF.
    4. Inspect for fuel leaks.
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