Are you experiencing some weird symptoms in your car like frequent engine misfires and the car is significantly down on power? Well, this is a really unfortunate situation because this might be caused by a bad ignition coil. But how to test coil pack without multimeter? More on that, we are going to elaborate in this article, where we will learn all the interesting details concerning this problem.
- Car Diagnostics?
- How The Ignition Works
- Ignition Coil?
- Wiring Diagram
- Bad Coil Symptoms
- How To Test?
Troubleshooting is a true mastery that you need to achieve in order to be able to uncover complex problems in your car. You need to have a proper understanding of how everything works and how car diagnostics is done the right way.
This is why reading how each component works and how interacts with other components is really important because sometimes the causes for a problem can be really minor and still make you pay a whole fortune replacing a component that doesn’t need replacing till you find the right culprit for a specific problem. That’s why we are going to help you out when it comes to testing coil packs and show you all the different methods.
But first, we will dive into the car diagnostic basics and learn how things are done for beginners. After that, we will cover the ignition system and then we will learn what is a coil and the 4 wire ignition coil diagram. Then we will discuss the symptoms and after that, we will learn how to test coil pack without multimeter. So, if you want to learn more, follow along.
Car Diagnostics Basics
Now before we dive into the problem and learn how to test coil pack without multimeter, let’s first take a look at what is car diagnostics and how it is done on modern vehicles. This will be extra useful for beginners who are new to cars and want to learn more about this stuff. So, if you are one of them, follow along, if not, move on to the following chapters where we elaborate more on the problem.
Nevertheless, modern car diagnostics is not like car diagnostics back in the day when problem-solving was only done by the mechanic and its experience.
Modern cars are a lot more complex and require a more modern approach. Nowadays vehicles come with dozen of different sensors and other electronic devices that are regulated by a component that is known as the car computer. You will also come across terms like ECU, PCM, or ECM. They are practically the same thing. The ECU is the brain of the car that regulates everything.
And in order for you to read the mind of the brain of the car, you need to have a special tool. This tool is also known as the OBD2 scanner device. All cars produced after 1996 are OBD2 compliant and you can get one of these scanners and scan the car for codes.
Then based on the codes that you collected. You can move on and start testing stuff. And for testing, you will need a multimeter. But unfortunately, in this case, you don’t have a multimeter. So, you need to learn how to test coil pack without multimeter.
And frankly, this is possible. Spark plugs and ignition coils can be tested without multimeter. Later on, we will explain how this is done.
Vehicle Ignition Parts
Now before we learn more about how to test coil pack without multimeter, let’s first take a look at how the ignition system works in a car. This will also be really useful for beginners because there are two types of these systems. The old school system with a single ignition coil and the modern individual ignition coils.
First, we are going to cover the old-school distributor type of ignition system. This is a system that is consisted of the battery, and ignition switch which is the key that you turn. Then there is the resistor or condenser as it is known and the single ignition coil.
This is a large coil that basically is a simple electrical transformer that creates a high tension circuit and then drives this strong current into the distributor. And from the distributor, this current travels through the wires and then to the spark plugs and ignites the gas.
Remember that this is the old school system that was used up till the 90s when it was replaced by a more modern system known as the individual coil.
So, this system is pretty much the same. The only difference is that instead of featuring a single ignition coil, distributor, and wires, it only features a coil pack that does all this at once. And in the following chapter, we are going to further explain how this ignition coil works and what it actually does. Then we will dive into the diagram and also how to test coil pack without multimeter.
What Is An Ignition Coil
Now before we learn more about how to test coil pack without multimeter, let’s take a look at what is ignition coil in general. What is this component, really?
Well, in simple words, an ignition coil is an electrical transformer. So, what does it transforms? Well, this ignition coil is supplied with the electric current from the battery. Which is 12V DC current.
Then, when it enters the coil, this electricity is converted into a very strong current that has thousands of volts. Which is enough to produce a spark. And then this strong electric current is sent to the spark plugs where the electrodes create the spark.
It is a really simple device that has an open magnetic circuit that creates a strong magnetic field that stores a lot of energy that is then transferred to the spark plug. But how to test coil pack without multimeter? Well, we are going to explain that further on, now let’s take a look a the 4 wire ignition coil diagram.
4 Wire Ignition Coil Diagram
Before we dive into the symptoms and how to test coil pack without a multimeter. Let’s take a look at the 4 wire ignition coil diagram. We will cover mainly the 4 wire ignition coil diagram. With a small focus also on the 2 wire ignition coil diagram as well as a 3 pin ignition coil wiring diagram.
So, modern cars usually run 4-pin ignition coils. And if you decide to test one with a multimeter you need to know what these wires are.
Generally, when it comes to these diagrams, it is worth mentioning that there are four wires. This is why it is called a 4-pin connector.
There is a 12V power supply that goes from the battery to the coil, then there is the ground wire. And there are two wires that transmit a signal to the ECU. IGF pin and IGT. The IGT is the 5V signal wire that delivers the input from the coil to the ECU. Depending on the performance of the coil which ranges from 0 to 5 volts.
The first wire is usually the 12V supply, then there are the two wires that go to the ECM and the last is the ground wire. But this can vary from manufacturer to manufacturer.
Three-pin connectors are a lot simpler. These do not have the IGF connector but only the IGT. So, it is ground wire, 12V supply, and 5V signal wire to the ECU.
Two pins are even simpler than this. You only get one negative ground wire and one power wire. These are usually the old-school coil packs found on vehicles that are running a distributor. Produced before 1996. But how to test coil pack without multimeter? More on that in a bit.
Bad Ignition Coil Symptoms
Now since we learned what is the ignition coil as well as the diagram of this component. We can now move on and cover the symptoms.
Knowing the symptoms is really essential when it comes to learning how to test coil pack without multimeter. So, in the following couple of chapters, we are going to cover them thoroughly and learn more about them.
How To Test Coil Pack Without Multimeter, Symptoms #1: Check Engine Light + Limp Mode
Now before we start learning the methods of how to test coil pack without multimeter, let’s discuss more about the first symptom that you will notice when a coil fails.
And this symptom is the check engine light. The check engine light as you probably know is a special light that indicates a problem with your engine.
Once you notice it, it is up to you to diagnose the car with a special tool known as an OBD2 scanner. This tool will tell you what type of problems your engine has.
Specific for ignition coils, you can get trouble codes ranging from P0350 to P0364. Also, other codes can be present like P0300 which indicates a random misfire. Or a misfire on a specific cylinder, for example, P0303. An indication that cylinder 3 has either a bad coil or a bad spark plug.
Also, another very common thing in some high-performance cars is the limp mode. When a coil fails, the car will go into limp mode and will not allow you to rev it too much. But only enough to take you home. Now let’s move on to the next symptom before we dive into how to test coil pack without multimeter.
How To Test Coil Pack Without Multimeter, Symptoms #2: Engine Misfires
The second very common symptom that we are going to cover before we learn how to test coil pack without multimeter is the situation when you experience misfires. So, what is a misfire?
Well, a misfire in simple words is a situation when you have either delayed ignition of the fuel or premature ignition. This means that the ignition is not evenly timed out.
So, when this happens, you will notice the check engine light in most cases and a code of P0300 or similar code that indicates a misfire.
Also, when you have a misfire, there will also be some ticks coming from the top of the cylinder heads where the spark plugs are located.
Also, at the exhaust, you will notice some pops and bangs as well as some black smoke because the fuel isn’t burning right and your car struggles to run. Now let’s move on to the next symptoms before we dive into how to test coil pack without multimeter.
How To Test Coil Pack Without Multimeter, Symptoms #3: Rough Idle
The next symptom that we would like to cover when it comes to this problem with the coil pack is the rough idle.
Whenever you start experiencing a bad ignition coil, the engine will idle pretty rough. Why so? Well, this is primarily due to the poor delivery of electric current from the ignition coil.
The coil will not produce the demanded current so the spark works continuously without any issues. So, when there are fluctuations like these, you will have problems with the idle.
You will notice how the RPM goes up and down on the odometer and there is basically rough engine work. So, if you notice when on idle happens something odd like this, then it is definitely worth checking it out and seeing if the sparks and coils are working well.
Later on, we will learn how to test coil pack without multimeter for the guys who don’t have a multimeter by their hand. Now let’s move on with the rest of the symptoms before we start diagnosing stuff.
How To Test Coil Pack Without Multimeter, Symptoms #4: Engine Down On Power
The next symptom that we would like to cover is the situation when the engine is significantly down on power.
And this will actually be the case. Why so? Well, imagine that one of the cylinders isn’t working well and you have four of them.
This means that the engine is running on three cylinders in total. So, 3 cylinders produce significantly less power in comparison to four cylinders.
You will easily lose 20hp or even more. The engine will be down on power and the car will feel sluggish and slow to respond.
So, if you notice something like this that the engine is losing so much power, you should definitely give it a look and learn how to test coil pack without multimeter.
This way, you will be able to determine if one or more of the coils that you are running is bad and doesn’t perform well. But how to test coil pack without multimeter, we will learn later on in the article. Now let’s move on to the next symptom.
How To Test Coil Pack Without Multimeter, Symptoms #5: Difficulty Starting & Engine Stalling
The next symptom that we would like to cover is the situation when you have difficulty starting the engine. Or the engine stalls right after you start it. So, why is this happening?
Well, the most common reason behind this problem is definitely because of either a bad spark plug or a bad ignition coil.
There is simply not enough electric current in order to keep the engine running properly and the engine simply turns off by itself.
Whenever you have a problem like this when the engine stalls. Better check the spark plugs and ignition coil. Just to make sure that these are not the components that make it fail. But how to test coil pack without multimeter? More on this we are going to cover in a moment.
How To Test Coil Pack Without Multimeter, Symptoms #6: Backfiring
And the last symptom that we are going to cover before we dive into how to test coil pack without multimeter is the situation when you have backfires.
Cars that often misfire also backfire as well. And this is one of the common outcomes when we are dealing with a situation like this when you have problems with the coils. But what does a backfire looks like? Does it burn?
Well, not quite. When a car backfires, it is usually accompanied by a large explosion occurring inside of the muffler when the fuel gets ignited. Now let’s move on and learn how to test coil pack without multimeter.
How To Test Coil Pack Without Multimeter
Now let’s learn how to test coil pack without multimeter. What you can do in order to determine what is the problem and which coil is defective?
There are two methods. The test light method. And coil removal while the car is working. Let’s cover them one by one.
How To Test Coil Pack Without Multimeter: Method 1
This method I wouldn’t recommend because it is rather dangerous for people who don’t know what they’re doing. But how does it work?
Well, it is rather simple. You first unscrew the coils and leave them inside of the cylinder. Then start the car. The car will be running and remove one of the coils.
Once removed, place a test light where the hole of the coil is located. If the coil is working, it will produce a constant spark that will be visible. If it doesn’t produce a spark, then the coil is probably bad.
How To Test Coil Pack Without Multimeter: Method 2
The second method is even simpler. It is called a power balance test. Just like with the previous method, you remove the screws of the coils and let them loose.
Start the engine and then remove one coil and wait. If there is a change in the work of the engine, it means that the coil is good. This means that it loses power.
If the engine work stays the same after you remove a coil, it means that the coil is probably defective and has to be replaced. How you can test both of these methods you can see in the video above. There are two timestamps, one for the first method and another for the second method.
Coil Pack Replacement
So, we learned more about how to test coil pack without multimeter, now let’s take a look at how you can replace the coil pack on your car.
This is a really simple procedure. Before you do this, make sure that you disconnect the positive terminal. In order for you not to get codes later on.
Then once there is no power in the car, just pop up the cover and unscrew the two screws that are holding the coil in. Once you did that, just pop out the connector and remove the coil from the engine.
Once you are done, just place the new coil in and then connect it accordingly. Connect the positive terminal and you will be good to go.
Coil Pack Cost
A single coil can cost from $100 to $250. It really depends on the car market and also the type of vehicle.
More expensive cars have considerably more expensive parts, so you really need to keep this in mind if you want to have things done on your car on a budget. Expensive cars require more money for maintenance.
In this article, we have covered quite a bit about ignition coils. First, we learned how modern car diagnostics is done the right way. Then we learned how the ignition works and how big of a role the ignition coil is playing in this process.
Then we covered the diagrams for all types of ignition coils and how they work. As well as the symptoms of bad ignition coils. Lastly, we learned how to test coil pack without multimeter.
Now let’s cover some frequently asked questions.
What Is A Coil Pack
A coil pack is a pack of ignition coils. Usually, a coil pack consists of 3 to 4 ignition coils. When changing coils, you don’t need to get a whole pack since replacing only the defective one will do the trick.
What Does An Ignition Coil Do
Ignition coils are small electric transformers that transform the 12V DC power into a very strong current that blasts the spark plugs and you get proper ignition inside of the cylinders.
How Many Ignition Coils In A V6
On a V6, there are six coils in total. So, two coil packs consisting of three coils. One coil per each of the cylinders. The coils are located on top of the valve covers and are usually covered by a plastic cover.
How Long Do Ignition Coils Last
Ignition coils usually last for 100,000 to 150,000 miles with no problems. But this isn’t always the case and a coil can fail prematurely sometimes. These are electric components and are prone to failure.
How To Tell If A Coil Pack Is Bad
If you get a trouble code like P0350 or a similar code or if you get a misfire code like P0300. If the car obviously misfires, runs rough, or stalls, then checking the coils should be your top priority. Also, the spark plugs can also cause misfires, so be aware of this as well.
Should I Replace Ignition Coils With Spark Plugs
You don’t have to if the spark plugs are good. But if they are old, you can replace them. They are really cheap anyways and will not cost you a fortune to replace them. The car will run much better with new spark plugs.