How to Replace Spark Plugs

Spark plugs are an important component of most modern engines. They are a part that one can easily replace. With little care and some tools, replacing spark plugs can be one of the most rewarding DIY task an individual can do. With a little care and very few tools, changing your spark plugs can be one of the most rewarding do it yourself projects an individual can do their vehicle. It is fairly easy and requires only 40 minutes for a V8.

Follow the directions.

Things Needed

  • Socket Driver
  • Swivel adapter for the driver allows for tight spaces
  • 3″ and 6″ drive extensions
  • 3/16 or 5/8 deep socket

Replace Spark Plugs


Step 1:

Before starting, get a service or repair manual for the specific model of your vehicle.

Step 2:

Make sure that the car is turned off before you begin.

Step 3:

Remove one spark plug wire from one spark plug by gripping the plug wire boot without the wire. A spark plug wire puller is better to use if available.

Step 4:

There should be no oil or dirt around the spark plug. Wipe the area around the spark plug hole if needed. Make sure that the oil and dirt is not brushed away from the hole.

Step 5:

Use proper tools to take out the plug, turn the plug anti-clockwise to the left. The appropriate tool for this task is a 5/8 or 13/16 deep socket. A swivel joint and an extension may also be needed.

Step 6:

This has to be replaced with a new one. The plug has to be turned by hand until it is tightened.

Step 7:

The same tool used for taking out the old one can be used to fit in the new one.

Step 8:

The spark plug wire has to be connected to the new plug and make sure it is on.

Step 9:

Replace all plugs by following the steps from 3 to 8.

Tips and Precautions

  • When you are at the auto store, a spark plug wire puller and a spark plug gaper is needed. Although the gap is already set on new plugs, it would be good to check it. The wire puller helps to save the wires from getting pulled apart.
  • By doing one plug at a time, everything will be kept in order. A plug wire that is crossed means that the vehicle will fire out of order or miss fire.
  • Examine the old spark plugs closely when you remove them. They are helpful in giving signs of how the vehicle is running.
  • Consider installing high quality plug wires while you are under the hood.
  • Diesel engines do not have spark plugs.

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