What Is Ignition Coil?

The ignition coil is a part of the vehicle ignition system. It is also called a spark coil and it basically is an induction coil. Its job is to transform the batter’s low voltage to the thousands Volta actually needed in order to create an electric spark in the spark plugs. This then helps the spark plugs to ignite the fuel.


There are several components to the ignition coil which enable it to perform its function. We will read all about this component along with how to install it in this article.

Types of Ignition Coil

There are three different types of ignition coils, below is information about them to help understand their differences and features:


  1. Conventional Ignition Coil - This can be in use since 1900s. In this type of system, the primary circuit of the ignition coil receives power from the battery via a resistor. This power is grounded through closed ignition points present in the distributor. The current flows through the windings of the primary coil, this creates a magnetic field. The points get open by the windings of the distributor cam, and the current’s electrical circuit gets broken, which then breaks the magnetic field. The force by which the magnetic field collapses, crosses the windings of the secondary coil, which then creates an electric current within them, and it’s this current which flow into the distributor cap. It moves through the distributor into the spark plug within a matter of a split second.
  2. Electronic Ignition Coil - These become well known in the mid-1970’s and are rather similar to the conventional system having the same configuration in the secondary circuit of the coil. The primary circuit is also the same from the battery to the coil terminal, however instead of having a distributor cam and points, this type of system uses a pickup coil in order to signal the control module. This fires the ignition coil. You may find the ignition coil located inside the distributor cap in some electronic systems.
  3. Distributor less Ignition Coil - This came out in the 1980s, and is designed to allow more energy to be available from the coils. There are typically more than three coils mounted together in the coil pack, unlike the two coils in other systems. Each of these is responsible for firing either one spark plugs or pair. The energy speed as well as the crankshaft position is determined using a magnetic triggering device. This device simply sends a signal to the engine control module/ignition control module which then sends energy to the coil.

How Do Ignition Coil Work?

The ignition system comprises of different components which have separate functions. All of them work together to be able to drive the process of ignition. Primarily the ignition process is where a spark produced by the spark plugs will trigger an explosion and ignite the air fuel mixture. This will power the engine as needed to function.


Your vehicle's ignition coil comes into the picture when the insufficient trigger by 12-volt battery used in the machine is produced to facilitate explosion. The coil converts the 12-volt power into 40kV as required to create the spark.


The contact breaker closes when the current from the battery starts to build up, this continue till its full capacity is reached. After reaching the full capacity point it opens and a high voltage spark is hence produced. Without the presence of the ignition coil, the 12v DC battery on board the vehicle is of no use. Few ignitions coils resort to resistor to be able to reduce the voltage, while others rely on a resistor wire or an external resistor to perform the same task.


Two coils of wire make up the ignition coil, they are placed one on top of the other. These are referred to as windings, ‘primary coil’ is the first one and the second one is referred to as the ‘secondary coil’. The secondary coil turns are in multiples of the number of turns in the primary coil. The current from the battery flows through the primary coil, and gets collected together to be able to produce the spark required, this is eventually sent by the secondary coil to the distributor. To be able to manage the heat generated during this process the coil is filled with oil, which behaves as a coolant. Few vehicles depending on their engine are equipped with a single ignition coil, while others have one for each spark plug.

Frequent Problems With Ignition Coil

Common ignition system complaints include:


  1. Complete no start of a vehicle - You may find that you’re not able to completely start your vehicle as usual.
  2. Difficulty when starting the vehicle - Without receiving the optimal signal from the ignition coil, the spark plugs can’t perform their job. Starting your vehicle may become even more difficult during cold or humid weather.
  3. Engine misfiring while running - During high speeds you may experience engine misfire, accompanied by jerking or loss of power.
  4. Lowered fuel economy - Insufficient energy created by the spark plug can cause the remaining cylinders to compensate for the loss of power, which increases the consumption of fuel.
  5. Engine stalls at idle - This may happen rather frequently if the ignition system isn’t working efficiently.

Symptoms Of Bad Ignition Coil?

Multiple issues may occur with a bad ignition coil, we have made note of the most common ones and how to resolve them:


  1. Engine misfires, rough idle, and loss of power - Being a central component of the ignition system, faults with the ignition coil can cause the vehicle to experience misfire, rough idle, and loss of power and acceleration. Gas mileage also get reduced drastically. You may also experience stalling due to these performance issues.
  2. Check Engine Light comes on - A problematic ignition coil, can cause issues leading to alerting about the problem via the check engine light on the dashboard. An issue picked up by the computer regarding the ignition coil signal or circuit can also cause this light to go off
  3. Car doesn’t start - A no-start condition is common with an inefficient or improper ignition coil. A faulty coil will impact the operation of the entire engine in case of single ignition coil vehicles. In case the coil has fully malfunctioned, it will leave the engine without spark, this will result in a no spark and no-start condition.

Tools Needed For Ignition Coil

Do you like repairing your car on your own? Thinking of opening up your own car body shop? It is a great business opportunity if you love cars and possess a good work ethic. Now if you want your shop to be successful, then you will require a combination of effort as well as car mechanic training. And of course, the correct equipment which would upgrade your speed as well as make your repair work easy. If you have the right tools, then you can easily meet the demands of today's car body structures. Here are some of the most essential tools which you might need to repair your Ignition coil.


Top Brand For Ignition Coil

If you know which car parts brand suits the best for your ignition coil, then it would save a lot of your decision-making time. What we believe is that picking a particular brand would always be helpful in reducing the clutter, and at the same time would make it easier for the customers to find what they are actually looking for. That’s why we have listed out some top brands for ignition coil below as follows:


Blue Streak (Hydride Motor) Ignition Coil

Richporter Technology Ignition Coil

Spectra Premium Industries Ignition Coil

Beck/Armley Ignition Coil

Delphi Ignition Coil

Related Parts Of Ignition Coil

If you are like most of us, then you won’t know much about the related components of car ignition coil. Fear not! Here is a quick and easy guide to explain the related parts of the ignition coil.


Total Costs & Repair Times, Effort For Ignition Coil

Failure in the ignition coil comes in a lot of forms. But take note that it is not an inexpensive repair. Sometimes in the end you might find out that there is a need of complete ignition coil replacement. There is no fast and hard number as to how much would an ignition coil replacement would cost as it depends upon a lot of factors like the brand, make, model as well as the mechanic who is going to repair/replace it. The average cost for an ignition coil replacement can be anywhere between $231 and $331. Labor costs can estimated to be from $59 and $75. The replacement parts can be purchased between $172 and $256. Estimate does not include taxes and fees.

How to Change Ignition Coil?

Here’s how you can change your vehicle's ignition coils step wise:


Step 1: Disconnect the battery


Start by disconnecting the negative cable of the battery to be able to cut off power to the vehicle. Using a socket or wrench you can disconnect the clamp bolt holding the cable to the terminal. Be careful while doing this.


Step 2: Locate the ignition coils


You can always use your vehicle manufacturers manual for assistance on this, however the ignition coil will be attached to the engine block or the surrounding components.


Step 3: Disconnect and remove the old ignition coil


Begin with disconnecting the bolts/screws which are attaching the coil to the vehicle. Also disconnect the electrical connectors from the coil carefully. Find out which connection has to be broken first, they may vary from vehicle to vehicle. So, refer your manufacturer's manual for this. It is important to mark or label these connectors so that you have no confusion while reassembly. The wires should get reattached to the correct corresponding connections to the new coil at the time of installation.


Step 4: Install the new ignition coil


In the reverse order of how you disconnected the old ignition coil, go ahead and install the new one. Pay special attention to the markings you made for the electrical connectors and ensure they all go in the right place.


Step 5: Reconnect the battery


Now you can reattach the negative battery terminal to the car battery and restore power to the vehicle. Using your hand, tighten the electrical connection and using a socket/wrench tighten down the terminal bolt securely. Be sure to not over-tighten the bolts, you want it to be tight enough to not cause any engine vibration to loosen them. Over tightening can result in damage. Close the hood and proceed on to the next step of testing your replacement.


Step 6: Test the new coil


Start your engine in park and test the new ignition coil If you are able to start the vehicle and it idles as normal then you can do on a test drive.