How To Test The Ignition Coils (1999-2001 1.6L Mazda Protege)

TEST 5: Testing For Spark At The Ignition Coil

If you've reached this point, then you got a no spark test result for either cylinder #2 or cylinder #4 in TEST 1. This test section applies to either test result.

As you're already aware, one ignition coil sits right on top of the #2 cylinder spark plug. This specific ignition coil simultaneously feeds spark to cylinders #2 and #3. The second ignition coil sits on top of the #4 cylinder spark plug. And this ignition coil simultaneously creates and feeds spark to cylinders #1 and #4.

With the above information in mind, I'm going to ask you to remove the ignition coil of the cylinder that's not getting spark (as confirmed in TEST 1) and check for spark one more time. I know that you've already done this in TEST 1. But checking for spark one more time will help us come to the right conclusion.

OK, let's get testing:

1. 1

   Remove the ignition coil from the valve cover. This is the ignition coil of the cylinder that is not getting spark in TEST 1.

2. 2

   Place the spark tester directly in the ignition coil boot. Your spark tester should be set up like in the photo above.

3. 3

   Ground the spark tester with a battery jump start cable to a good engine Ground point or directly on the battery negative (-) terminal.

4. 4

   Have your assistant crank the engine. The engine may start, so be careful.

5. 5

   You're gonna' get one of two results: spark or no spark.

Let's take a look at what your test results mean:

CASE 1: The spark tester DID spark when checking for spark for cylinder #2. This result lets you know that the ignition coil is good only if you have confirmed that cylinder #3 is getting spark.

In other words: The ignition coil is designed to fire off spark simultaneously to both cylinders (#2 and #3). So, if your spark tester has confirmed that this ignition coil is feeding spark to cylinders #2 and #3, then this ignition coil is good and not defective.

CASE 2: The spark tester DID spark when checking for spark for cylinder #4. This result lets you know that the ignition coil is good only if you have confirmed that cylinder #1 is getting spark.

In other words: The ignition coil is designed to fire off spark simultaneously to both cylinders (#1 and #4). So, if your spark tester has confirmed that this ignition coil is feeding spark to cylinders #1 and #4, then this ignition coil is good and not defective.

CASE 3: The spark tester DID NOT spark when checking for spark for cylinder #2. If in TEST 1 you verified that this same ignition coil is firing off spark to cylinder #3, then you can conclude that the ignition coil is bad and needs to be replaced.

I'll explain: The ignition coil is designed to fire off spark simultaneously to both cylinders (#2 and #3). If it's only firing spark to one of the two cylinders (in this case cylinder #2), then you can conclude beyond a shadow of a doubt that the ignition coil is bad.

CASE 4: The spark tester DID NOT spark when checking for spark for cylinder #4. If in TEST 1 you verified that this same ignition coil is firing off spark to cylinder #1, then you can conclude that the ignition coil is bad and needs to be replaced.

I'll explain: The ignition coil is designed to fire off spark simultaneously to both cylinders (#1 and #4). If it's only firing spark to one of the two cylinders (in this case cylinder #1), then you can conclude beyond a shadow of a doubt that the ignition coil is bad.

TEST 6: Misfire Due To Carbon Tracks

So you got spark from all of the spark plug boots and ignition coil boots, but you're still experiencing a Misfire Condition. Well it could be carbon tracks that have developed on the inside of the high tension wires and ignition coil boots that are diverting the spark to Ground.

Carbon tracks inside the spark plug boot (whether the boot belongs to one of the two spark plug wires or the ignition coil itself) are common occurrences in this type of ignition system. Not only that, but a leaking valve cover gasket will inundate the spark plug tubes with engine oil causing a misfire too.

What does a carbon track look like? Take a look at the photos of the image viewer and you'll see what one looks like inside the boot and on the spark plug.

If you do find traces/evidence of a carbon track, you've got to replace both the spark plug and the spark plug wire or ignition coil that has the corresponding carbon track on it. Carbon tracks can not be cleaned or removed.