Testing the ignition coils (most commonly known as the COP ignition coils), on your 1.8L Nissan Sentra is pretty easy. You don't need any expensive diagnostic equipment to see if they have failed and causing the misfire code or condition your Nissan Sentra is currently experiencing.
In this tutorial, I'll show you how to test them in a detailed step-by-step fashion.
Let's get started with some basic info...
The Coil-on-Plug (COP) ignition coils are the ones that create and deliver the Spark that each engine cylinder needs to burn the air/fuel mixture.
When one COP ignition coil fails... that cylinder goes ‘dead’ due to a lack of Spark and is said to be misfiring.
The most obvious symptom of bad cop ignition coil, is a miss at idle and when you accelerate your Nissan down the road.
You're also gonna' see the check engine light (CEL) shining nice and bright on your instrument cluster and one (or several) of the following:
If your vehicle is experiencing any of the above symptoms, chances are that you do have a BAD COP Coil on your hands. Let's take a look at some of the basic tools you'll need to diagnose and repair this yourself.
The most important tool that you're gonna' need, to test the ignition coils for spark, is a spark tester.
I'm gonna' recommend one that is the most effective (and the most inexpensive) out there: the HEI spark tester (KD Tools 2756).
From personal experience (I work full-time as an automotive tech)... the HEI spark tester is a must have tool. You don't need to interpret the color of the spark or the weakness of it. With the HEI spark tester... if it sparks... the ignition coil is good.
NOTE: You run the risk of damaging a good COP ignition coil by pulling the ignition coil off of the spark plug while the car is running (to listen for the audible clicking sound the spark makes). Also, this way of checking the COP ignition coil for spark doesn't produce an accurate test result. This is why a spark tester becomes a must have tool.
Although it's not absolutely necessary to know how the Coil-on-Plug COP ignition coils work on your Nissan vehicle... I've included a brief description of how they work (for those of you who love to read the how and why of stuff).
In a nutshell, the COP ignition coil's job is to create and deliver spark to the spark plug.
Having an individual ignition coil per cylinder allows for a more maintenance free ignition system... since you have less moving parts that may wear out and that eventually need to be replaced... like:
Now, in case you're really curious about how it works... below is a very brief description of the whole process:
OK, with this brief overview of how the COP ignition coil works on your 1.8L equipped Nissan, let's turn the page and get testing...
“This planet has - or rather had - a problem, which was this: most of the people living
on it were unhappy for pretty much of the time. Many solutions were
suggested for this problem, but most of these were largely concerned
with the movement of small green pieces of paper, which was odd
because on the whole it wasn't the small green
pieces of paper that were unhappy!”
The Hitchhiker's Guide to the Galaxy