How do I Test a GM Coil Pack?

The coil pack is an indispensable part of your General Motors vehicle. It controls the ignition spark that is sent to each of your vehicle's cylinders to get them pumping and get your vehicle moving. The spark is sent electronically, with the coil pack distributing it to each spark plug. After you remove your GM coil pack, testing it out with a multimeter ensures that it emits the right voltage when it sends the sparks out.

Things You'll Need

  • Multimeter
  • Find the male spade terminal parts on the coil pack. They will be the two metal parts in the middle that are smaller than the rest of the ones found on the pack.

  • Turn the multimeter on. Attach the its red lead to the right terminal, then attach the black lead to the left terminal.

  • Read the voltage displayed on the multimeter. Your coil pack is properly powered if the reading is 11 to 12 volts.