Spark Plug: Service and Repair

Figure 1 Spark Plug Identification:

Figure 2 Spark Plug Installation:

Warning: If you smoke while handling coated spark plugs, wear gloves to prevent transfer of coating to cigarette and subsequent burning of coating. Always wash hands after handling coated plugs.

^ Allow engine to cool BEFORE removing spark plugs. Attempting to remove spark plugs from a hot engine may cause plug to seize, causing damage to cylinder head threads.

^ Clean spark plug recess area BEFORE removing plug. Failure to do so can result in engine damage due to dirt or foreign material entering cylinder head, or in contamination of cylinder head threads. Contaminated threads may prevent proper seating of new plug.

^ Use only spark plugs specified for use in the vehicle. DO NOT install spark plugs that are either "hotter" or "colder" than those specified for the vehicle. Installing plugs of another type can severely damage the engine. Spark plugs are identified as shown in.

Remove or Disconnect
1. Ignition key "OFF."
2. Engine acoustic cover.
3. Generator.
4. Ignition coil pack.

Caution: Pull on spark plug boot or heat shield only, twisting a half turn to release seal while removing. DO NOT pull on wire or spark plug lead may be damaged.

5. Plug wires from spark plugs. Note position of wires BEFORE removing.
6. Spark plug(s) from engine.

Caution: It is important to check the gap of all new and reconditioned spark plugs before installation. Pre-set gaps may have changed during handling. Use a round wire feeler gage to be sure of an accurate check, particularly on used plugs. Installing plugs with the wrong gap can cause poor engine performance and may even damage the engine.


Measure
Spark plug gap on plugs to be installed.


Install or Connect

Caution: Be sure plug threads smoothly into cylinder head and is fully seated. Use a thread chaser if necessary to clean threads in cylinder head. Cross-threading or failing to fully seat spark plug can cause overheating of plug, exhaust blow-by, or thread damage. Follow recommended torque specifications carefully. Over or under-tightening can also cause severe damage to engine or spark plug.

1. Spark plug(s) to engine. Tighten spark plug(s) to 20 Nm (15 lb. ft.).
2. Plug wires to spark plugs.
^ To proper location noted when removed.
3. Ignition coil pack.
4. Generator.
5. Engine acoustic cover.