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How to Replace Spark Plugs in a Pontiac Bonneville

by Contributor

The Pontiac Bonneville spark plugs are designed to last between 50,000 and 100,000 miles, depending on their tip quality. Spark plugs in a Bonneville need to be inspected and cleaned every 30,000 miles. Clean and efficient spark plugs increase fuel efficiency and decrease engine corrosion.

Step 1

Locate the spark plug wires on the sides or top of the Bonneville engine. Do not attempt to touch or remove anything from the engine until it is cool. Wrap a small piece of masking tape around every spark plug wire on the engine and number them in the order the spark plugs are removed.

Step 2

Twist the spark plug wire 180 degrees to the right and 180 degrees to the left at the boot, or end, that is attached to the spark plug. Pull up or out to remove the wire.

Step 3

Connect the socket, extension and wrench together and until it locks in place. Slide the socket onto the spark plug and turn it to the left to unscrew and remove the spark plug.

Step 4

Apply a generous coat of silicon dielectric compound to the thread and top of the new spark plug.

Step 5

Insert the new spark plug into the socket and thread it into the cylinder well. If resistance is met while threading, stop and try threading it again.

Step 6

Test the amount of tension on the plug with a tension tester tool. The appropriate tension is specified on the spark plug packaging.

Return all of the spark plug wires to the correct spark plugs. If a spark plug wire is placed on the wrong plug, the engine will misfire damage the machine. Turn the spark plug to lock the wires into place.

Items you will need

  • Masking tape
  • Marker
  • Spark plug socket
  • Socket wrench and extension
  • Silicon dielectric compound
  • Tension test tool

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