How to Diagnose a Bad Coil Pack

Written by alibaster smith
  • Share
  • Tweet
  • Share
  • Email

A bad coil pack on your vehicle will prevent the spark plugs from firing properly. Each spark plug on your vehicle has a coil pack, so if you suspect a problem with a coil pack, you may want to check all of them. To diagnose a bad coil pack, you'll need to use a voltmeter with an "Ohms" setting. The "Ohms" setting can measure continuity. This is the resistance of the coil pack and will determine if your vehicle's coil packs are providing the electrical spark that your spark plugs need.

Skill level:

Things you need

  • Voltmeter

Show MoreHide


  1. 1

    Set the dial on your voltmeter to "Ohms."

  2. 2

    Touch one of the leads on the voltmeter to one of the electrical terminals on the coil pack. There are two terminals: one on the top of the coil pack and one on the bottom. It does not matter which lead from the voltmeter touches which terminal on the coil pack. Then, touch the other lead on the voltmeter to the other terminal on the coil pack.

  3. 3

    Check the resistance. The display on the voltmeter should read between "0.0" and "0.05" Ohms. If it reads higher than "0.05" Ohms, then you need to replace the coil pack.

Don't Miss

  • All types
  • Articles
  • Slideshows
  • Videos
  • Most relevant
  • Most popular
  • Most recent

No articles available

No slideshows available

No videos available

By using the site, you consent to the use of cookies. For more information, please see our Cookie policy.