How to Replace a Distributor Cap

a metal distributor cap
  • 1-2 hours
  • Beginner
  • 15-35
What You'll Need
Nut driver or screwdriver
Distributor cap
Spark plug wires
Masking tape

A distributor cap is one of the easiest parts to replace on your vehicle. The distributor cap is a part of the ignition system in many older vehicles. It takes the electrical charge when you turn the ignition switch and routes it to the spark plugs in the correct firing order. The distributor cap is the device that covers the wires and other components that make up the distributor. Follow the simple steps below to effectively replace your distributor cap.

Step 1 – Buy the Distributor Cap

The distributor cap and rotor can be specific to the car or truck you have. To replace it, you need to get the right one for your vehicle. Go to the auto parts store and tell them the year, make and model of your vehicle. They will be able to sell you the correct cap and rotor.

Step 2 – Unplug the Cap

Open the hood to your vehicle and locate the distributor cap. It's easy to spot as it is black, gray or white and has several wires connected to it. There will also be a wire running from the distributor cap to the ignition coil. These are in place by firing order, and it is very important to get them connected correctly. As you remove one wire, always wrap it with a piece of masking tape and write the number on it for which it fires in. The wires typically just pull off of the cap. Your auto store may also have a reference chart for the firing order of your vehicle.

Step 3 – Remove the Cap

The distributor cap is mounted to the distributor by either screws or clips. If yours has clips, then push them in and twist them to the left. Otherwise, use the screwdriver to remove the screws on the cap. You may also use a nut driver or wrench depending on the size of the screw (or if they happen to be nuts). Do not misplace the screws.

Pull up on the distributor cap to remove it. With the cap removed, you will now see the rotor. You can remove this by either lifting it up or by twisting it all the way to the left like a screw cap.

Step 4 – Install the Distributor Cap

Begin replacing the distributor cap by replacing the rotor, which can easily be worn out. It will either set in place or you will need to twist it on like you would a lid to a jar. Once the rotor is properly seated, you can then place the new distributor cap in place. It will only go on one way, making it easy to install. Once it's in place, you can then attach it in the same manner as you used to remove it. Follow the chart or your notes to replace the wires you removed with the new wires.