Replace all eight spark plugs on the 5.0L Coyote V8 engine, including removal of ignition coils and proper gapping of new plugs.

Warnings

Tools required

Parts

• Spark plugs - Motorcraft SP-534 or equivalent × 8 — Motorcraft SP-534

Preparation

1. Ensure engine is completely cold (at least 2 hours after last operation)
2. Disconnect negative battery terminal to prevent accidental cranking
3. Remove engine cover by releasing clips and removing mounting screws
4. Label ignition coil positions 1-8 using tape or take photos for reference during reinstallation
5. Verify all replacement spark plugs are correct specification for 5.0L Coyote engine

Procedure

1. 1

   Remove engine cover
   Release the engine cover clips by pulling upward, then remove the cover mounting screws. Lift the engine cover assembly away from the engine to expose both valve covers and ignition coils.
   Torque spec

   Cover Screws14 Nm (10 lb-ft)

   Engine Cover Clips3 Nm (3 lb-ft)
2. 2

   Disconnect ignition coil connectors - passenger side
   Starting with cylinders 1-4 on the passenger side, press the release tab on each ignition coil electrical connector and pull straight up to disconnect. Keep track of connector positions as they may have different wire routing.
3. 3

   Remove passenger side ignition coils
   Using a 7mm socket, remove the single bolt securing each ignition coil (cylinders 1-4). Pull each coil straight up with a slight twisting motion to break the seal. Inspect coil boots for damage or oil contamination.
   ⚠If oil is present in spark plug wells, valve cover gaskets may be leaking and should be addressed before continuing
   Torque spec

   Ignition Coil Bolt14 Nm (10 lb-ft)
4. 4

   Clean spark plug wells - passenger side
   Use compressed air to blow out any debris, dirt, or oil from each spark plug well. Foreign material falling into the cylinder during plug removal can cause engine damage. Ensure wells are completely clean and dry.
5. 5

   Remove passenger side spark plugs
   Using a 5/8 inch spark plug socket with extension, carefully loosen each spark plug by turning counterclockwise. Once loose, unthread by hand to prevent cross-threading. Remove plugs and inspect electrodes and insulators for abnormal wear, fouling, or oil contamination.
   ⚠Use care not to drop socket or extension into engine bay - ensure tools are secure before use
6. 6

   Disconnect ignition coil connectors - driver side
   Move to cylinders 5-8 on the driver side. Press the release tab on each ignition coil electrical connector and pull straight up to disconnect. Note the connector positions and wire routing.
7. 7

   Remove driver side ignition coils
   Using a 7mm socket, remove the single bolt securing each ignition coil (cylinders 5-8). Pull each coil straight up with a slight twisting motion to break the seal. Inspect coil boots for damage or oil contamination.
   Torque spec

   Ignition Coil Bolt14 Nm (10 lb-ft)
8. 8

   Clean spark plug wells - driver side
   Use compressed air to blow out any debris, dirt, or oil from each spark plug well on the driver side. Ensure all wells are completely clean and dry before proceeding with plug removal.
9. 9

   Remove driver side spark plugs
   Using a 5/8 inch spark plug socket with extension, carefully loosen each spark plug by turning counterclockwise. Once loose, unthread by hand to prevent cross-threading. Remove plugs and compare condition across all eight cylinders for diagnosis.
10. 10

    Prepare new spark plugs
    Check the gap on all new spark plugs using a gap tool - spec is typically 0.051-0.057 inches for this engine (verify on plug box). Apply a small amount of anti-seize compound to the threads of each plug, keeping compound away from the electrode area to prevent fouling.
    ⚠Use anti-seize sparingly - excess can affect torque readings and lead to over-tightening
    Torque spec

    Spark Plug25 Nm (19 lb-ft)
11. 11

    Install new spark plugs
    Thread each new spark plug by hand into the cylinder head, ensuring it starts smoothly without resistance. If resistance is felt, remove and restart to avoid cross-threading. Once hand-tight, use torque wrench to tighten to specification in a smooth, continuous motion.
    ⚠️Never use an impact wrench on spark plugs - always use a calibrated torque wrench to prevent thread damage
    Torque spec

    Spark Plug25 Nm (19 lb-ft)
12. 12

    Reinstall ignition coils
    Apply a small amount of dielectric grease to the inside of each coil boot. Install coils into their original positions, pressing down firmly until seated. Install and torque the 7mm retaining bolt for each coil. Reconnect all electrical connectors, ensuring they click into place.
    Torque spec

    Ignition Coil Bolt14 Nm (10 lb-ft)
13. 13

    Reinstall engine cover
    Position the engine cover back onto the engine, ensuring all clips align properly. Press down on clip locations to secure, then install and torque the cover mounting screws. Reconnect the negative battery terminal.
    Torque spec

    Cover Screws14 Nm (10 lb-ft)

    Engine Cover Clips3 Nm (3 lb-ft)

Reassembly

1. Verify all ignition coil electrical connectors are fully seated and locked
2. Ensure engine cover is properly secured with all clips engaged and screws torqued
3. Double-check that no tools or parts were left in the engine bay

Verification

• Reconnect battery and start engine - it should start smoothly without extended cranking
• Allow engine to idle and listen for any misfires or rough running
• Check for diagnostic trouble codes using OBD-II scanner - there should be no misfire codes
• Rev engine gently to 2000-2500 RPM and verify smooth acceleration with no hesitation
• Inspect around valve covers and engine cover for any loose connections or forgotten fasteners

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