Mazda Check Engine Light – Learn the Causes and Fixes

Check engine light is one o the most feared thing in the car community. Also if you have Mazda, you may have a check engine light on. This means you need to deal with the problem if you know the causes. Here we discuss abıut Mazda check engine light. And also you can find out about the general fixes that you can apply. And you will have the information about the general prices of the fixing.

What are the Causes of Mazda Check Engine Light?

Mazda symbol.

There are various common possibilities for the check engine light. If you know the exact problem and the symptoms, it will be very easy to detect and apply the fix.

Loose Fuel Cap

Lots of people have this problem. If the fuel cap is loose for your Mazda car, you will get a check engine light on the dashboard. This is a very common and the most basic thing that you can face. And we wish that the only problem that you have is this.

And also the solution to this problem is very simple. You just need to squeeze your fuel cap strictly into its place. And you will be able to drive your car without checking the engine light.

Also, low fuel can make the Mazda check engine light on. You just need to add a sufficient amount of oil to your engine.

Also, we can give a very good joke idea that you can make for your friend or relatives that have a Mazda car 🙂 You just need to loosen the gas cap of the Mazda car of your friend and make the Mazda check engine light on in the dashboard. When your friend sees it, he or she will be shocked. But do not hold the joke too long. Just say you made a joke and loosened the gas cap to make the check engine light on 🙂

Problems with Coils and Spark Plugs

This is also a very common problem with the ignition systems of your car. The spark plug in your car engine and cylinders must ignite the air-fuel mixture when the cylinder is at the top dead center of the cylinder. There is a spark that will ignite the fuel. So, if you have a problem with this system, the Mazda check engine light will on the dashboard.

Also, you can feel the power and performance of your engine drop. This power drop can result in very bad problems for you.

If a spark plug does not work properly, the fuel that comes into the cylinders will not burn properly. Also if you have a problem with the distributor system which provides electricity to all the spark plugs in each cylinder, the engine simply will not work.


The general fix for this problem is to change the spark plug with a new one. Checking one spark plug of a Mazda engine will cost around $150 including the labor cost.

Also if there is a problem with your alternator, changing with a new one can cost around $350-$400 including the labor cost. Because the OEM parts of alternators can cost around $200 and the labor cost can be $150-$200. Because ripping off and repairing alternators is not an easy thing to make.

Also, there can be problems with the cable systems that connect the spark plugs with the alternator and the battery. Checking one cable can make the cost around $50.

High Emissions

Mazda check engine light.

Also if there is a problem with the emiisioıns of your Mazda car, the Mazda check engine light will be on. Your car must expel a specific amount of emission of exhaust gases. And there is a part that is called a catalytic converter that converts the poisonous gases into the less poisonous way. And if there is a problem with the catalytic converter, your emissions will get worsen. The sensors can measure these emissions and make the check engşine light open.

Fixing the Emission Problems of Mazda

Most of the problems with the emissions can result from the catalytic converter that your car has. There can be two reasons that the catalytic converter of your car does not work properly.

The first reason is the clogged channels of the converter because of the carbon buildup. You can feel that thing as an engine performance loss. Because if the channels of catalytic converters are clogged, the engine will use much more power to expel the exhaust. In this case, you need to clean the catalytic converter of your car.

If you are familiar with car mechanics, you can easily do it on your own. You just need to rip the catalytic converter off from the exhaust system of your car at the bottom. If you have basic wrenches or screwdriver sets, you can easily solve the problem. You just need to use the general solutions to clean the converter channels according to the instructions of these solutions.

But also your catalytic converter can be damaged. This is a very common problem because there can be damage coming from the road to the bottom of the Mazda. You can understand that your catalytic converter has been damaged by the strange noises coming from the exhaust system.

The only solution for it is to change the catalytic converter with a new one. The general prices of catalytic converters of the Mazda change around $350-$400 in the market in general. And if we add labor costs, you will probably pay around $500.

Problems with Thermostat

Also, you can face problems with your thermostat. If your car has a faulty thermostat, the Mazda check engine light will be on. The main duty of the thermostat is to adjust the temperature of the engine. It starts the cooling system of the engine to lower the temperature and heat. And if you have a problem with the thermostat of your engine, you will feel it as an engine heat increase.

So, at the dashboard, if you see the engine temperature border and check engine light is on, you can easily understand that you have problems with your thermostat.

Fixing the Thermostat

You just need to bring your car to a car mechanic to deal with the thermostat problem of your car. So, they can easily fix the problem with your thermostat.

Changing the thermostats of the Mazda car is generally cost will be around $200-$250 including labor costs. So, it will be very good to deal with the thermostat.

In this case, you just need to bring your car to Mazda service. This is a problem that you can not solve on your own.

Oxygen Sensor Problem in Mazda Engine

Also if you’re seeing Mazda check engine light on the dashboard, you can easily understand that you have a problem with the oxygen sensor. The oxygen sensor is responsible to send information about the amount of oxygen in the exhaust fumes. The ECU system adjusts the best amount of fuel to the cylinders according to this information to create the best ignition inside the engine cylinders.

If there is a problem with the oxygen sensor, you can feel it as an engine power and performance loss. And misfire will be another symptom if you have an oxygen sensor fault.

Fixing Oxygen Sensor Faults

There can be several reasons for the oxygen sensor faults of the Mazda engines. The first one is, there can be carbon buildup on the oxygen sensor. If there is a lot of carbon on the sensor, the sensor can not read the amount of oxygen in the exhaust fumes. You can rip off the oxygen sensor and clean the carbon buildup on the sensor. You need to use some special fluids to do this. And you can find these fluids in the market. And apply cleaning to the sensor according to the instructions.

The place of the oxygen sensor is right after the catalytic converter. You need to lift the car with a proper hydraulic or mechanical jack to reach the bottom of the car. If you have a basic wrench or screwdriver set, it is very easy to remove the fasteners to take the sensor. Also, you need to remove the cable connections to the battery and ECU system.

Also, if you have problems with the cable connections, you need to check the connections if they are connected well or not. And also if there are damages to cables, changing these cables can cost around $50-$75 per cable.

Also, the oxygen sensor of your Mazda engine can be directly the problematic part of your car. You just need to change it with a new one. As we explained above, you can change it on your own. You just need to make the connections well. Also if you are not familiar with the car mechanics, you need to bring your car to a Mazda service. The total costs will be around $250. The cost of the OEM sensor is around $100-$150. And labor and expertise costs will be around $100.

Problem with Mass Air Flow Sensor

If you have problems with your mass air flow sensor, you will feel the same symptoms as the problems with the oxygen sensor of your Mazda engine. The main reason for this, the mass air flow sensor sends the information of total airflow comes to the intake manifold to the ECU system. And ECU system adjusts the best amount of fuel according to the oxygen informaitın and air information that it takes from the sensors.
So, it is very important to know this information.


First of all, all the information about the costs of oxygen sensor fixes is the same as an oxygen sensor.

Also, you can not change the mass air flow sensor and it requires expertise to do it.

Last Words on Mazda Check Engine Light

As you see above we explained the general causes and fixes of the Mazda check engine light problem. Also, we explained the general costs of the general fixes in different scenarios.

And we explained what you can solve on your own and what you can not.
If you have additional comments and questions about this topic, please leave them below. Your precious feedbacks are very important to us!


GMC Check Engine Light – What are the General Causes?

Volkswagen Check Engine Light – Causes, Fixes and Prices

Jeep Check Engine Light – Causes, Fixes and Prices

Hyundai Check Engine Light – Common Causes and Fixes

Buick Check Engine Light – Common Causes and Solutions


Mazda Users Manuals – Mazda USA

The Most Common Mazda Problems – Get Jerry

Genuine Mazda Parts – Mazda USA

Uğur Uygun

Hello everyone, I am Uğur. I am a mechanical engineer who has experience in different R&D departments of HVAC companies. With my best friend, I decided to build this website to share out knowledge and experience. And also, I am interested in automotive. So, I am writing about automotive and automotive-related articles here. Sharing my knowledge and experiences on these topics is a very big pleasure for me. I am willing to answer all of the questions people have about these topics.

Related Articles

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Back to top button