This procedure covers the replacement of the fuel pressure regulator on the 2021-2024 Ford F-150 with 3.5L EcoBoost V6 engine, including fuel system depressurization and component removal.

Warnings

Tools required

Parts

• Fuel pressure regulator × 1 — Use OEM Ford specification
• Fuel line O-rings × 2 — Use OEM Ford specification
• Pressure regulator gasket/seal × 1 — Usually included with regulator

Preparation

1. Park vehicle on level ground and engage parking brake
2. Ensure engine is completely cold (minimum 2 hours after last operation)
3. Disconnect negative battery terminal and wait 5 minutes to allow fuel pump capacitor to discharge
4. Remove engine cover by pulling upward on front edge and lifting off mounting grommets
5. Place shop towels around fuel rail area to catch residual fuel spillage
6. Review location of fire extinguisher before beginning fuel system work

Procedure

1. 1

   Relieve fuel system pressure
   Locate the fuel pressure test port on the fuel rail (passenger side of engine). Remove the Schrader valve cap and attach fuel pressure gauge. Open gauge valve slowly to bleed pressure into a suitable container until gauge reads zero. Close valve and remove gauge. Reinstall Schrader valve cap.
   ⚠️Wear safety glasses during pressure relief. Residual fuel may spray from test port.
2. 2

   Disconnect fuel line connections
   Locate the fuel supply and return lines connected to the fuel rail. Use appropriate fuel line disconnect tool to release the quick-connect fittings. Push tool into fitting while pulling fuel line away from rail. Cap or plug open fuel lines immediately to prevent contamination. Inspect O-rings on line ends for damage.
   ⚠Expect residual fuel to drain from lines. Have drain pan or towels ready.
3. 3

   Remove fuel rail assembly
   Disconnect fuel injector electrical connectors (6 total) by pressing release tabs and pulling straight up. Remove the four fuel rail mounting bolts using 8mm socket. Carefully pull fuel rail assembly upward to disengage injectors from intake manifold. Wiggle gently if resistance is felt but do not force. Set fuel rail assembly on clean work surface.
   Torque spec

   Fuel Rail Bolts23 Nm (17 lb-ft)
4. 4

   Access fuel pressure regulator
   With fuel rail removed, locate the fuel pressure regulator mounted on the fuel rail assembly (typically at driver side end). Note the orientation and position of vacuum line connection if equipped. Disconnect vacuum line by pulling straight off barbed fitting.
5. 5

   Remove pressure regulator mounting screws
   Using appropriate driver, remove the regulator mounting screws securing the pressure regulator to the fuel rail. There are typically 2-3 screws depending on regulator design. Keep screws organized for reinstallation or replacement.
   ℹ️If screws are damaged or thread-locking compound is deteriorated, replace with new hardware.
   Torque spec

   Regulator Mounting Screws5 Nm (4 lb-ft)
6. 6

   Remove fuel pressure regulator
   Carefully pull the pressure regulator straight out from the fuel rail bore. Slight twisting motion may help break seal. Remove and discard old O-ring or gasket from regulator mounting surface and fuel rail bore. Clean mounting surface on fuel rail with clean, lint-free shop towel. Inspect bore for damage or debris.
7. 7

   Install new fuel pressure regulator
   Lubricate new O-rings with clean engine oil or fuel and install on new pressure regulator per manufacturer instructions. Insert new regulator into fuel rail bore, ensuring proper orientation matches original position. Press firmly until fully seated against mounting surface.
   ⚠Do not use petroleum jelly or non-compatible lubricants on O-rings. Use only fuel or clean engine oil.
8. 8

   Secure pressure regulator
   Install regulator mounting screws and tighten in a cross pattern to ensure even seating. Torque to specification using inch-pound torque wrench. Reconnect vacuum line if equipped by pressing firmly onto barbed fitting until fully seated.
   Torque spec

   Regulator Mounting Screws5 Nm (4 lb-ft)
9. 9

   Reinstall fuel rail assembly
   Inspect injector O-rings and replace if damaged. Align fuel injectors with intake manifold ports. Press fuel rail assembly down evenly until all injectors are fully seated. Install four fuel rail mounting bolts and torque to specification in a cross pattern. Reconnect all six fuel injector electrical connectors until they click into place.
   Torque spec

   Fuel Rail Bolts23 Nm (17 lb-ft)
10. 10

    Reconnect fuel lines
    Install new O-rings on fuel line fittings if required. Push fuel supply and return lines onto fuel rail fittings until they click into place. Pull back on each line to verify secure connection. Ensure safety clips are properly engaged on quick-connect fittings.
    ℹ️If new O-rings were used on line fittings, ensure they are properly seated before connecting lines.
11. 11

    Restore power and prime fuel system
    Reconnect negative battery terminal. Turn ignition key to ON position (do not start engine) for 5 seconds, then OFF. Repeat this cycle 3-4 times to prime fuel system. Inspect all fuel connections for leaks during priming cycles.
    ⚠️If any fuel leaks are observed, immediately turn ignition OFF and repair leak before proceeding.
12. 12

    Start engine and verify operation
    Start engine and allow to idle. Inspect all fuel connections and regulator mounting area for leaks. Check fuel pressure at test port with gauge if available (should read 40-60 PSI at idle for EcoBoost). Listen for smooth idle operation. Reinstall engine cover when verification is complete.

Reassembly

1. Ensure all fuel line connections are fully seated and safety clips engaged
2. Verify all electrical connectors are properly latched
3. Reinstall engine cover by aligning grommets and pressing down firmly until seated
4. Remove all shop towels and tools from engine bay

Verification

• With engine running at idle, verify no fuel leaks at regulator, fuel rail connections, or fuel lines
• Check for proper fuel pressure at test port (40-60 PSI at idle)
• Confirm smooth engine idle with no rough running or hesitation
• Rev engine to 2000 RPM and verify fuel pressure remains stable
• Allow engine to reach operating temperature and recheck for leaks
• Verify no fuel odor in engine bay or cabin after test drive

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