How to Test Ignition Coil without Multimeter | Step-by-Step Guide

In any vehicle, the ignition coil is the most essential part of an engine vehicle.  It uses the battery voltage and transforms it into thousands of volts. This high voltage creates a spark that helps in igniting the fuel engine. Thus, if the ignition coil fails to perform its operation, you would be standing still watching your vehicle not getting started at all!

If our vehicle is stalling or not starting overall then these are signs that we need to replace the ignition coil. But before replacement, we need to inspect the condition of the ignition coil. The best way to test an ignition coil is using a automotive multimeter to directly measure the voltages but in case you don’t have a multimeter, this article is for you!

Follow the below mentioned steps that explains how to test the ignition coil without multimeter:

Gather the safety equipment:

Your first priority should be your safety. So, firstly take proper tools including safety glasses and eye protection. These would save you from getting an electric shock from a faulty spark plug or coil. Do this before playing with the spark plug or ignition coil!

Locate the ignition coil:

Now, after wearing the safety equipment, the next step is to locate the ignition coil inside your engine.  For that, firstly turn off the engine of the vehicle and open the hood and search for the ignition coil.

The location of the ignition coil inside the hood depends on the vehicle type. Its location would be different in your car, jeep or truck. So, find its location according to its placement.

However, most of the time, it is present close to the fender or it is present inside a bottle-type structure near to the distributer.

But, if we have such type of vehicle, which doesn’t have any distributor and we are unable to identify that where the ignition coil is then identify the spark plug instead of distributer and see its connections. You will see that the ignition coil directly connected to the coil.

Observe the misfire and swap the coils:

After finding the ignition coil, closely observe the misfire in some cylinders of the vehicle engine. If any of the ignition coils is faulty, you’ll see a misfire in any one or more cylinders. Identify that particular cylinder having a misfire.

Let’s say we have cylinder 2 that is having a misfire having coil on plug packs. Now, we’re partially sure that it’s faulty and causing the issue but how would we make sure that the fault isn’t in the cylinder itself?

To prove that, we’ll swap the ignition coils located in different cylinders. In our example, we’ll remove the coil of cylinder 2 and swap it with the one of cylinder 5.

Always clear the codes of your engine by using the code reader before performing the testing. If you are unaware of your engine code then first identify this according to your vehicle type from the internet.

Observe misfiring after replacing the coils:

Now, turn on the engine and leave it running for few minutes. If the coil of cylinder 2, which is swapped with the coil of the 5th one earlier, is faulty, then it would be causing misfiring in cylinder 5 as well. It ensures that the fault is not in the cylinder itself but within the coil itself. Now, you’ll have to take your car to a specialized mechanic so that he can replace it on time.

However, even after replacing the coil, misfiring is occurring in the same cylinder, there is nothing wrong with the ignition coil. So, going for your maintenance vehicle to a nearby mechanic would be the sane decision.


can you drive with a bad ignition coil

Yes, it’s possible to drive with a bad ignition coil but, it isn’t recommended. As, soon as you feel that there is something wrong with your ignition coil, get it inspected by a certified mechanic. You may not feel any difference driving with a bad ignition coil, but deep inside, it could cause serious harm to not only the engine cylinders but the rest of the components as well. So, don’t take it lightly.

Can an ignition coil get weak?

Although, nearly all ignition coils are pretty reliable and lasts for years but still, it’s a mechanical component that can get weak. Still, it can be repaired easily and you won’t need to replace it every time it goes bad.

Can a bad ignition coil cause a misfire

Yes, an ignition coil causing misfiring is one of the earlier symptoms of a faulty ignition coil. If you observe continuous misfiring, get it inspected by a mechanic as it could harm the other engine parts as well.

Final Thoughts!

This is how you can test the ignition coil without a multimeter. Although this process doesn’t require any tools for diagnosing the faults, it’s a bit time-consuming. Moreover, it’s less reliable as one may not hear any misfiring but it’s actually happening inside the cylinder. So, in spite of being a straightforward approach, you should go for testing the ignition coil with a multimeter.

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