How to Replace Spark Plugs

Some routine maintenance, like changing your car’s spark plugs, can easily be done on your own. We’ll tell you how to replace spark plugs in about an hour. All you need are a few tools and supplies.

What You Need

Allow yourself 40-60 minutes, and make sure you have the following supplies ready:

1. Spark Plug Socket
2. Spark Plug Gap Gauge
3. 3/8” Ratchet
4. Ratchet Extensions
5. 3/8” Swivel Socket
6. Compressed Air Canister
7. Protective Goggles

How to Replace Spark Plugs

1. First, make sure your engine is cold and check your vehicle owner’s manual to verify that you have the correct spark plugs. The use of incorrect spark plugs is severely detrimental to your engine.
2. Put on your goggles, and use the compressed air to clean the spark plug area thoroughly.
3. Disconnect the first spark plug wire by gently tugging on the boot and twisting to the right and left to loosen it. Only remove one spark plug wire.
4. Attach the spark plug ratchet to the spark plug and turn counterclockwise to loosen it. Remove it by hand once it is loose enough.
5. Insert the gap gauge between the bottom and the hook of the spark plug. These are the inner and outer electrodes. Measure the gap and compare it to the vehicle owner’s manual or the specifications listed under the car hood. Bend the hook lower or higher, if necessary, to create a gap that matches your vehicle’s specifications.
6. Clean the cylinder thread area with compressed air if you see visible dirt.
7. Screw the replacement spark plug in by hand until it is firm. Tighten it with the spark plug ratchet.
8. Reattach the spark plug wire, twisting to position the boot above the plug. You will hear a click when the wire and spark plug have connected properly.
9. Repeat steps 3-8 for each remaining spark plug, replacing one at a time.

Biggers Mazda for Great Service

Now you know how to replace spark plugs. Some maintenance tasks are not as simple. Biggers Mazda is your source for all your service needs, from routine maintenance to complex repairs. Contact us today for more information.