How To Test The Ignition Coils (1998-2001 2.5L Ford Ranger)

TEST 4: Primary Ignition Coil Tower Spark Tests (Paired Cylinders)

Testing The Ignition Coils -Misfire Condition (1998, 1999, 2000, 2001 2.5L Ford Ranger And Mazda B2500)

IMPORTANT: This test only applies if in TEST 1 you had 2 spark plug wires that did not spark and they connect to paired cylinders. Paired cylinders are cylinders that get spark simultaneously. They are cylinders #1 and #4 or cylinders #2 and #3.

In this test section, we're gonna' check for spark directly on the ignition coil towers of the spark plug wires that did not fire off spark in TEST 1.

If both towers do not spark, then you can confidently conclude that the primary ignition coil is defective.

If both towers spark, you can conclude that the spark plug wires are defective.

Let's get testing:

  1. 1

    Disconnect the spark plug wire that did not spark in TEST 1 from its ignition coil tower.

  2. 2

    Place the spark tester in the ignition coil tower. This is the coil tower that you just removed its high tension wire.

  3. 3

    Ground the spark tester directly to the battery negative (-) terminal using a battery jump start cable.

  4. 4

    Have your helper crank and start the engine while you observe the spark tester.

  5. 5

    The spark tester should spark with the engine running.

  6. 6

    Repeat the spark test on the other ignition coil tower whose spark plug cable did not spark in TEST 1.

Let's analyze your spark test result:

CASE 1: The spark tester sparked on both towers. This is the correct test result and lets you know that the primary ignition coil pack is good.

This test result also tells you that the spark plug wires (high tension wires) that connect to these 2 coil towers are defective. Replace all of the 8 spark plug wires with a new set.

Spark plug wires will eventually stop transmitting spark from the ignition coil to the spark plug. This is a very common problem.

CASE 2: The spark tester DID NOT spark on both towers. This test result lets you know that the primary ignition coil pack is probably defective and needs to be replaced.

To be sure (it's defective), you need to make sure that the ignition coil is getting its activation signal. If cylinders 1 and 2 coil towers are not sparking, go to: TEST 7: Verifying The Activation Signal For Cylinders 1 And 4.

If cylinders 2 and 3 coil towers are not sparking, go to: TEST 8: Verifying The Activation Signal For Cylinders 2 And 3.

CASE 3: The spark tester sparked on only one tower. This test result lets you know that the primary ignition coil pack is defective and needs to be replaced (because both should be sparking).

TEST 5: Secondary Ignition Coil Tower Spark Test

Testing The Ignition Coils -Misfire Condition (1998, 1999, 2000, 2001 2.5L Ford Ranger And Mazda B2500)

IMPORTANT: This test only applies if only one of the four spark plug wires of the secondary ignition coil did not spark in TEST 3.

What we're going to do in this test section is to check for spark directly on the secondary ignition coil tower of the high tension wire that did not spark in TEST 3.

If the spark tester sparks, then you can conclude that the spark plug wire is defective. If the spark tester does NOT spark, you can conclude that the secondary ignition coil pack is defective.

NOTE: The spark tester must be held in place in the ignition coil pack tower. You can easily and safely do this by Grounding the spark tester with a battery jump start cable. The battery jump start cable will make it easy (and safe) to hold the spark tester in the coil tower.

These are the test steps:

  1. 1

    Disconnect the spark plug wire that did not spark in TEST 3 from its secondary ignition coil tower.

  2. 2

    Place the spark tester in the ignition coil tower. This is the coil tower that you just removed its high tension wire.

  3. 3

    Ground the spark tester directly to the battery negative (-) terminal using a battery jump start cable.

  4. 4

    Have your helper crank and start the engine while you observe the spark tester.

  5. 5

    The spark tester should spark with the engine running.

Let's analyze your spark test result:

CASE 1: The spark tester sparked. This is the correct test result and lets you know that the secondary ignition coil pack is good.

This test result also tells you that the spark plug wire (high tension wire) that connects to this coil tower is defective. Replace all of the 8 spark plug wires with a new set.

Spark plug wires will eventually stop transmitting spark from the ignition coil to the spark plug. This is a very common problem.

CASE 2: The spark tester DID NOT spark. This test result lets you know that the secondary ignition coil pack is defective and needs to be replaced.

Ford Vehicles:

  • Ranger 2.5L
    • 1998,
      1999,
      2000,
      2001

Mazda Vehicles:

  • B2500 2.5L
    • 1998,
      1999,
      2000,
      2001