Installation Procedure

2025 Chevrolet Trailblazer LS, 1.2L Eng VIN PSECTION Installation Procedure
  1. GM5389725Courtesy of GENERAL MOTORS COMPANY
    NOTE:
    • The camshaft MUST be at the base circle position before the fuel pump is installed.
    • At the base circle position, the EN-52443  High Pressure Fuel Pump Alignment Tool will sit flush with the cylinder head.

    Install the EN-52443  High Pressure Fuel Pump Alignment Tool (2) with the Number 1 (1) on the outside and turn the crankshaft until the camshaft lobe is at the base circle position.

  2. Remove the EN-52443  High Pressure Fuel Pump Alignment Tool (2).
  3. GM5389726Courtesy of GENERAL MOTORS COMPANY

    Lubricate the fuel injection pump shaft lifter roller (1) with engine oil. Adhesives, Fluids, Lubricants, and Sealers

  4. Fuel Injection Pump Shaft Lifter Roller (1) - Install
  5. GM6163433Courtesy of GENERAL MOTORS COMPANY

    Fuel Pump Housing Seal (1) - Install NEW

  6. NOTE:

    The fuel pump flange must be fully seated to the cylinder head.

  7. Fuel Pump (2) - Install
  8. CAUTION:

    Alternately hand-tighten the fuel pump bolts one turn at a time until the pump is fully seated. Trying to draw down the pump without even side-to-side tightening may result in pump plunger damage.

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.