How to replace the spark plugs

Tools and Supplies

1. Spark Plugs
2. Socket set with spark plug socket or spark plug wrench
   
3. Torque wrench
4. Rag or paper towels
5. Penetrating oil
6. Wire feeler gauge and gapping tool

Let's start...

Firstly, mark each ignition wire and corresponding spark plug location with a number on a piece of masking tape.

Secondly, we need to disconnect the ignition wire or coil packs. Pull the plug cable boot straight out to disconnect each cable. On models with individual ignition coil packs, pull the coil pack straight out. Some engines may require you to remove the top cover in order to access the plugs.


Then, it is the time to remove the spark plugs. If you can reach the base of the spark plug, apply penetrating oil where it seats to the cylinder head. This will protect the threading in the cylinder head. remove each spark plug and its metal washer with a spark plug wrench or spark plug socket.







The forth step is to inspect the old spark plug that just taken out. For more information regarding spark plug, please refer to Spark Plug Firing End Analysis.. After that, remove old spark plug washers from the spark plug holes.







Next is to set spark plug gap. Using a wire feeler gauge, check the gap between the electrodes to the correct clearance. Carefully bend the outer electrode as required to feel a slight drag on the wire gage.