This procedure covers the removal and replacement of the knock sensor(s) on the 2015-2020 Ford F-150 5.0L V8 Coyote engine, which are located in the engine valley beneath the intake manifold.

Warnings

Tools required

Parts

• Knock sensor × 1 — Use OEM Ford knock sensor
• Intake manifold gasket set × 1 — Use OEM specification
• Coolant (if draining system) × 2 — Motorcraft Orange Coolant

Fluids

• Motorcraft Orange Coolant — 2 qt

Preparation

1. Ensure engine is completely cool to the touch
2. Disconnect negative battery terminal and wait 10 minutes
3. Remove engine cover by pulling upward on retaining clips
4. Relieve fuel system pressure if applicable to your specific work area
5. Place drain pan under vehicle and prepare for coolant spillage
6. Take photos of vacuum lines, electrical connections, and hose routing for reference

Procedure

1. 1

   Remove Air Intake System
   Disconnect the mass airflow sensor electrical connector. Loosen the clamp at the throttle body. Remove the air intake tube by lifting upward and away from the engine bay. Remove the air filter housing if additional clearance is needed.
2. 2

   Disconnect Throttle Body and EVAP Connections
   Disconnect the throttle position sensor electrical connector at the throttle body. Disconnect the EVAP purge valve line and electrical connector. Label each connection for reassembly reference.
3. 3

   Remove PCV and Vacuum Lines
   Disconnect the PCV hoses from the valve covers. Remove any vacuum lines connected to the intake manifold, taking note of their positions. Use plastic pry tools to avoid damaging quick-connect fittings.
4. 4

   Disconnect Fuel Lines and Coolant Hoses
   Using the appropriate coolant line disconnect tool, disconnect the heater hoses and any coolant bypass lines at the intake manifold. Have a drain pan ready as coolant will drain from these lines. Disconnect fuel lines if they interfere with manifold removal.
   ⚠Coolant will drain when lines are disconnected. Catch in a clean container for reuse if coolant is fresh.
5. 5

   Disconnect Fuel Injector Harness
   Disconnect all fuel injector electrical connectors. Unclip the fuel injector wiring harness from the intake manifold and position it aside. Note the routing for correct reinstallation.
6. 6

   Remove Intake Manifold Mounting Bolts
   Remove the intake manifold mounting bolts in a reverse spiral pattern from outside to inside. There are typically 8 bolts securing the manifold. Keep bolts organized by location as some may be different lengths.
   Torque spec

   Mounting Bolts60 Nm (44 lb-ft)
7. 7

   Remove Intake Manifold
   Carefully lift the intake manifold assembly straight up and away from the engine. You may need to gently rock it side-to-side to break the gasket seal. Place the manifold on a clean work surface. Cover the open valley with clean shop towels to prevent debris entry.
   ⚠Do not pry between the manifold and heads as this can damage sealing surfaces.
8. 8

   Locate and Access Knock Sensors
   Remove the shop towels temporarily to locate the knock sensors. On the 5.0L Coyote, there are typically two knock sensors located in the valley between the cylinder heads, mounted to the engine block. Clean the area around the sensors before removal.
9. 9

   Disconnect Knock Sensor Electrical Connector
   Press the release tab and disconnect the electrical connector from the knock sensor. Inspect the connector for corrosion or damage. Clean if necessary with electrical contact cleaner.
10. 10

    Remove Knock Sensor
    Using the appropriate socket and extension, carefully remove the knock sensor by turning counterclockwise. The sensor should come out easily once fully unthreaded. Inspect the sensor mounting boss on the block for damage or debris.
    ℹ️Do not allow the sensor to drop into the valley. Keep a firm grip during removal.
11. 11

    Clean Sensor Mounting Location
    Clean the knock sensor mounting boss thoroughly with brake cleaner and a shop towel. Ensure the mounting surface is completely clean and free of old gasket material, oil, or debris. The sensor must make proper contact for accurate operation.
12. 12

    Install New Knock Sensor
    Thread the new knock sensor into the mounting boss by hand until finger-tight. Ensure the sensor threads in smoothly without cross-threading. Using a torque wrench, tighten the sensor to specification. This torque value is critical for proper sensor function.
    ⚠Proper torque is essential. Under-tightening causes poor sensor contact; over-tightening damages the sensor crystal.
    Torque spec

    Knock Sensor20 Nm (15 lb-ft)
13. 13

    Reconnect Knock Sensor Electrical Connector
    Reconnect the electrical connector to the knock sensor, ensuring it clicks firmly into place. Verify the connection is secure by gently tugging on the connector.
14. 14

    Clean Intake Manifold Gasket Surfaces
    Using a plastic gasket scraper, carefully remove all old gasket material from both the intake manifold and cylinder head mating surfaces. Clean thoroughly with brake cleaner and lint-free towels. Surfaces must be completely clean and dry for proper sealing.
    Torque spec

    Gasket Surface Bolts26 Nm (19 lb-ft)
15. 15

    Install New Intake Manifold Gaskets
    Position the new intake manifold gaskets on the cylinder heads. Ensure gaskets are properly aligned with all bolt holes and coolant passages. Some gaskets may have alignment pins or tabs to assist with positioning.
    Torque spec

    Gasket Bolts25 Nm (19 lb-ft)
16. 16

    Reinstall Intake Manifold
    Carefully lower the intake manifold into position, ensuring it seats evenly on both gaskets. Do not force the manifold down. Start all mounting bolts by hand before tightening any of them. Tighten bolts in a spiral pattern from center outward to specification using a torque wrench.
    Torque spec

    Mounting Bolts60 Nm (44 lb-ft)
17. 17

    Reconnect All Components
    Reconnect all fuel injector electrical connectors, throttle body connector, EVAP lines, vacuum lines, PCV hoses, fuel lines, and coolant hoses in reverse order of removal. Reference photos taken during disassembly. Ensure all connections are secure and properly seated.
18. 18

    Refill Coolant System
    Refill the cooling system with the appropriate Motorcraft Orange Coolant to the proper level. Burp the cooling system according to Ford procedures to remove air pockets.
19. 19

    Reinstall Air Intake System
    Reinstall the air intake tube and air filter housing. Tighten the throttle body clamp securely. Reconnect the mass airflow sensor electrical connector. Reinstall the engine cover.
20. 20

    Reconnect Battery and Clear Codes
    Reconnect the negative battery terminal. The vehicle may need to relearn idle characteristics. If a check engine light was present for knock sensor codes, they should clear after successful repair and drive cycle completion.

Reassembly

1. Double-check all electrical connections are secure and properly seated
2. Verify all vacuum lines and coolant hoses are connected and clamped properly
3. Ensure no tools or shop towels were left in the engine valley
4. Check coolant level in overflow tank after engine reaches operating temperature

Verification

• Start the engine and check for coolant leaks around the intake manifold
• Listen for any vacuum leaks or unusual noises
• Allow engine to reach operating temperature and verify cooling system is functioning properly
• Use a scan tool to verify knock sensor is reading properly (typically 0-2.5V at idle)
• Test drive the vehicle and monitor for knock sensor codes using a scan tool
• Verify no check engine light illuminates and knock sensor readings are within normal range during acceleration

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