Spark Plug: Service and Repair

When replacing the spark plug and coil cables, route the cables correctly and secure them in the appropriate retainers. Failure to route the cables properly can cause the radio to reproduce ignition noise, cross ignition of the spark plugs or short circuit the cables to ground.

CAUTION: Never attempt to tile the electrodes or use a wire brush for cleaning platinum plugs. This would damage the platinum pads which would shorten spark plug life.

Never force a gap gauge between the platinum electrodes or adjust the gap on platinum spark plugs without reading the Spark Plug Gap Measurement procedures below.

Always tighten spark plugs to the specified torque. Over tightening can cause distortion resulting in a change in the spark plug gap. Overtightening can also damage the cylinder head. Tighten spark plugs to 28 Nm (20 ft. lbs.) torque.

Due to the engine packaging environment for these engines, extreme care should be used when installing the spark plugs to avoid cross threading problems.

SPARK PLUG GAP MEASUREMENT

CAUTION: The Platinum pads can be damaged during the measurement of checking the gap if extreme care is not used.

Setting Spark Plug Electrode Gap:

- Use only a taper gap gauge.
- Never force the gap gauge through the platinum pads. Only apply enough force until resistance is felt.
- Never use a wire brush or spark plug cleaner machine to clean platinum spark plugs
- Use an OSHA approved air nozzle when drying gas fouled spark plugs.

Platinum Made:

If gap adjustment is required of platinum plug, bend only the ground electrode. DO NOT TOUCH the platinum pads. Use only a proper gapping tool and check with a taper gap gauge.

Apply a very small amount of anti-seize compound to the threads when reinstalling the vehicle's original spark plugs that have been determined good. Do not apply anti-seize compound to new spark plugs.

NOTE: Anti-seize compound is electrically conductive and can cause engine misfires if not applied correctly. It is extremely important that the anti-seize compound doesn't make contact with the spark plug electrodes or ceramic insulator.

SPARK PLUG REMOVAL-# 2, # 4 or # 6
Always remove the ignition cable by grasping at the spark plug boot turning, the boot 1/2 turn and pulling straight back in a steady motion.
1. Prior to removing the spark plug spray compressed air around the spark plug hole and the area around the spark plug.
2. Remove the spark plug using a quality socket with a rubber or foam insert.
3. Inspect the spark plug condition.

INSTALLATION
1. To avoid cross threading, start the spark plug into the cylinder head by hand.
2. Tighten spark plugs to 28 Nm (20 ft. lbs.) torque.
3. Install ignition cables over spark plugs.

SPARK PLUG REMOVAL # 1, # 3 or # 5
1. Disconnect negative cable from auxiliary jumper terminal.
2. Remove the intake manifold.
3. Always remove the ignition cable by grasping at the spark plug boot turning, the boot 1/2 turn and pulling straight back in a steady motion.
4. Prior to removing the spark plug spray compressed air around the spark plug hole and the area around the spark plug.
5. Remove the spark plug using a quality socket with a rubber or foam insert.
6. Inspect the spark plug condition.

SPARK PLUG INSTALLATION
1. To avoid cross threading, start the spark plug into the cylinder head by hand.
2. Tighten. spark plugs to 28 Nm (20 ft. lbs.) torque.
3. Install ignition cables over spark plugs.
4. Install the intake manifold.
5. Tighten air inlet tube clamps to 3 Nm ± 1 (25 ± 5 in. lbs.) torque.
6. Connect negative terminal to auxiliary jumper terminal.