The 5.4-liter displacement engine used in Fords, sometimes called the Triton engine, was first installed in a 1997 Ford F-150 as the largest engine option that year. The 5.4-liter engine was also used at the base power plant in the heavier Super Duty trucks. These engines use a coil on plug ignition system, which utilizes an ignition coil for each cylinder. This may be an efficient system, but it makes finding, let alone removal, of the spark plugs more difficult than in other V-8 engines.
Open the hood.
Remove the three retaining bolts from the black plastic engine cover with a 10-mm wrench.
Lift the engine cover straight up, and place it aside.
Loosen the hose clamps on either end of the air intake hose on top of the engine with a Phillips screwdriver. Pull the small hoses near the fuel injection system out of the intake hose, and push them aside. Pull the intake hose straight up, and place it aside.
Remove the three retaining screws that hold the air-filter housing on top of the engine in place with an 8-mm wrench. Lift the housing straight up, and place it aside.
Locate the coil-on-plug (COP) assemblies, which are mounted over each spark plug. Remove the COPs by removing the retaining bolt with a 7-mm wrench. Press in on the release tab on the COP wiring plug, then pull the plug straight out. Twist the COP out, and remove it to reveal the spark plug underneath. Repeat this procedure for each COP if desired.
