How to Replace Spark Plug Wires

Is it time for a new set of spark plug wires? This article will save you some headache when replacing your spark plug wires.

Difficulty: Moderately Easy

Instructions

Things You'll Need:

• New Spark Plug Wires

1. 
   Properly Routed Spark Plug Wires.

   The best way to install new spark plug wires is one at a time. If you remove all of them at once you may not remember what order they went in, or how they were routed. This can result in a spark plug wire being on the wrong spark plug which will cause a misfire.

2. 
   Spark Plug Wire With Rubber Boot.

   The best way to remove a spark plug wire from the spark plug is to grab the top and twist it back and forth while you pull it out. This will make it easier to remove it. Some spark plug wires have a rubber boot on the bottom of them where the spark plug wire sits on the spark plug. You can see it in the picture near the spark plug hole. These can sometimes prevent a problem. When you pull the spark plug wire out, this little rubber boot will sometimes stay behind. If it does, you won't be able to put a socket on the spark plug, or install the new spark plug wire. To remove it straighten out a metal coat hanger. At the very end bend it back so that it looks like a "J". Insert the coat hanger into the spark plug hole. Try to get it between the spark plug and the boot. Now turn it slightly so that the hook is facing towards the rubber boot. Pull the coat hanger out slowly. It may take a couple of tries, but the boot should come out with the coat hanger.

3. 
   Distributor Cap.

   Now remove the spark plug wire from the distributor cap. Use the same twisting method that you used to remove the spark plug wire from the spark plug. With the spark plug wire removed, hold it up and find the new spark plug wire that is the same length. Take the new spark plug wire and push it down onto the distributor cap. You may or may not hear a click. To see if it is properly seated, gently pull back on the spark plug wire. If it does not come off easily then it is seated correctly. Now place the other end onto the spark plug. Push down on the spark plug wire. You will most likely hear a click. If you do, then the spark plug wire is seated properly. To be sure, gently pull back on the spark plug wire. If it does not easily come out then it is correctly installed.

4. 
   Seperated Spark Plug Wires.

   Repeat this process for all of the spark plug wires. You should try to keep them separated as much as you can. Notice the picture. You don't want them to look like a bird's nest. This could eventually lead to a misfire. The spark will start to shoot through the spark plug wires to each other and not to the spark plug.

Tips & Warnings

• Replace one spark plug wire at a time. This will prevent you from routing them improperly. You don't want the #2 spark plug wire going to the #4 cylinder.
• Do not remove a spark plug wire while the vehicle is running. Trust me, it hurts. I have to do this for diagnosis a lot, and I can tell you it is better than the morning coffee for waking you up.

Resources

• How To Change Spark Plugs
• Spark Plug Wires

[Traqqer]

on 2/3/2009 These are great, practical tips. I won't have to go to the mechanic for this now.