How To Test The Coil Pack (1990-1998 Chrysler 3.3L, 3.8L)

This is a complete diagnostic test of the ignition coil pack that's used on the 1990-1998 3.3L, 3.8L V6 engines on Chrysler cars and mini-vans.

With the help of this article, you'll be able diagnose a malfunctioning ignition coil pack and or troubleshoot diagnostic trouble code (DTCs) P0300, P0301, P0302, P0303, P0304, P0305, P0306 (if your Chrysler car is OBD II equipped).

If this is not the Chrysler V6 coil pack test you need, there are two more and you can find them at: 3.3L, 3.8L Main Index Of Articles.

Important Tips

TIP 1: Read the entire article first. Familiarize yourself with what the tests are going to accomplish. It seems like a lot of reading and/or a complicated testing procedure, but it's not, as you'll see once you start the actual testing on your vehicle.

TIP 2: Before you do the actual tests on your car or mini-van, it's important the you know what ‘Paired Cylinders’ and ‘Non-Paired Cylinders’ mean to successfully diagnose a bad coil pack.

TIP 3: You'll be working in the engine compartment while the car or mini-van is cranking or starting, so be alert and take all necessary safety precautions. Think safety all of the time.

TIP 4: Since you'll need a helper to crank the engine for you, have him or her wait outside of the vehicle before and after you need them to crank the engine. This is important, since it will save you from having your helper crank the engine accidentally as your installing or removing a spark plug wire or the spark tester.

TIP 5: The coil pack test described in this article is an on-car test. Although you'll see the coil pack removed from the engine in the photos I'm using, the coil pack is removed from the vehicle (in the photos) just to make it easier to explain the tests.

What Tools Do I Need

To successfully use this information to diagnose and troubleshoot your Chrysler (or Dodge or Eagle or Plymouth) mini-van, you need a few specific tools. Don't worry, none of this stuff is expensive.:

1. A 12 Volt automotive test light.
2. A multimeter (don't have a digital multimeter? Need to buy one? Click here to see my recommendations: Buying A Digital Multimeter For Automotive Diagnostic Testing).
3. An LED light.
   • To see what this tool looks like, click here: The LED Light Test Tool And How To Make One.
4. An HEI spark tester
   • This tool is a must have (don't have an HEI spark tester? Need to buy one? You can buy it here: OTC 6589 Electronic Ignition Spark Tester).
5. Battery jump start cables.
6. Someone to help you crank the car.

The most important tool of the bunch that you should use for the tests indicated in this article is the HEI spark tester and it's NOT because I own the company that makes the HEI spark tester (If I did, I'd be spending the week it takes me to write an article, like this one, at the lake, I'm just a little nobody just giving back to the internet DIY auto community). The principal reasons are:

1.) This tool is accurate. It will give a true dependable result that is not based on the color of the spark to figure out if the spark is weak or good. If the HEI spark tester sparks, the spark is good and strong. If it does not spark, then you've got a bonafide no-spark result you can take to the bank.

2.) This tool is inexpensive. The only thing that sucks is that at the moment, your local auto parts store does not carry it, you have to buy it online, but because this spark tester is extremely accurate, it's well worth the wait.

Where To Buy The Ignition Coil And Save

The following links will help you comparison shop for the ignition coil pack:

Not sure if the above ignition coils fit your particular vehicle? Don't worry, once you get to the site they'll make sure it fits by asking you the specifics of your vehicle. If they don't fit, they'll find you the right ones.

COIL PACK TEST 1: Checking For Spark

Before you start this test, you must be aware of the principle behind ‘Paired Cylinder’ and ‘Non-Paired Cylinder’. Knowing the difference between both is very important. So before you start, take a look at the section: How The Coil Pack Works..

Also, to successfully accomplish this test without complications, please read the section: Precautions, Do's And Don'ts.

The first order of business is to find out if all the spark plug wires are delivering spark or not to the spark plugs. You don't have to test all of the spark plug wires, although if I where in your shoes, I would. For more info on this, see/read the section: Do I Need To Test All Of The Spark Plug Wires.

You'll need someone to help you to crank the engine. OK, this is what you'll need to do:

1. 1

   Remove the spark plug wire from the spark plug and connect the HEI spark tester to the spark plug wire.

2. 2

   Using a jump start cable, Ground the HEI spark tester directly on the battery negative (-) terminal.

3. 3

   When everything is set up, have your helper crank the engine while you eyeball the spark tester.

4. 4

   You'll see one of two results: spark or no-spark jumping across the air gap of the HEI spark tester.

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

CASE 1: You got spark from all six spark plug wires. Then this result indicates that the ignition coil pack and the spark plug wires are OK. The cause of the misfire is somewhere else.

CASE 2: You got a no-spark result from only one spark plug wire. This result either means that the spark plug wire is bad or the ignition coil pack is fried. Both can be tested and for this test, got to COIL PACK TEST 2.

CASE 3: You got a no-spark result from two ‘Paired Cylinder’ spark plug wires. This spark test result could mean that the coil pack is fried. To further verify/confirm this, got to COIL PACK TEST 3.

CASE 4: You got a no-spark result from two ‘Non-Paired Cylinder’ spark plug wires. This result either means that the spark plug wire is bad or the ignition coil pack is fried. Both can be tested and for this test, go to: COIL PACK TEST 2.

CASE 5: You got a no-spark result from all of the spark plug wires. This is not good, but doesn't condemn the ignition coil pack as bad yet. The next step is to make sure that the ignition coil is getting power (12 Volts) and then see if the Powertrain Control Module (Fuel Injection Computer) is activating the ignition coils within the coil pack. Go to: COIL PACK TEST 4.