Instead, if possible, you’ll want to test the ignition module to verify it’s the issue. The process of testing your module is heavily reliant on the model you have to work with.

The first step in replacing ignition coils is determining the type., Depositphotos Here’s How To Diagnose and Test An Ignition Coil Let’s do this!

Testing the ignition control module is a little trickier. When the module is exposed to a specific heat range—which can vary—it tends to fail. Therefore, the test may not be accurate.

CD ignition use a separate coil and ignition box along with the distributor, and the system makes it easy to fire a really hot spark all the way through the rpm range.

The HEI distributor is an inductive-discharge-style ignition, but with the points replaced by a solid-state switching device called an electronic ignition-control module.

To ensure that the test was fair, we had to make this distributor as good as new, or better. So, before it ever saw action, the stock distributor was treated to a new rotor, cap, and module.