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Ignition Coil Test

  1. Turn ignition off. Remove engine cover. Disconnect distributor lead and wiring from ignition coil.
  2. Place DVOM on high scale. Connect DVOM as shown in step 1 of illustration. See Fig 1. If reading is not infinite, replace ignition coil.
  3. Place DVOM on low scale. Connect DVOM as shown in step 2 of illustration. See Fig 2. If reading is not 0.1 ohm, replace ignition coil.
  4. Place DVOM on high scale. Connect DVOM as shown in step 3 of illustration. See Fig 3. If reading is not 5000-25,000 ohms, replace ignition coil.
  5. Reconnect distributor lead and wiring to ignition coil. Install engine cover.
Fig 1: Testing Ignition Coil - Step 1
G98B01081Courtesy of GENERAL MOTORS CORP.
Fig 2: Testing Ignition Coil - Step 2
G98D01082Courtesy of GENERAL MOTORS CORP.
Fig 3: Testing Ignition Coil - Step 3
G98F01083Courtesy of GENERAL MOTORS CORP.
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