Do Diesel Cars Have Catalytic Converters? (Yes or No)

Do Diesel Cars Have Catalytic Converters

Catalytic converters only came into existence in 1975, after it became required for every vehicle to have a catalytic converter to control the emissions from each vehicle.

Without a catalytic converter, the fume from cars becomes toxic to the environment, and this can cause a lot of damage.

However, the toxic fume is mostly a result of gasoline, so, since diesel is different, do diesel cars have catalytic converters?

Yes, diesel cars have catalytic converters. However, since diesel cars are very different from gasoline cars, their catalytic converters work entirely differently as well.

What are Diesel Cars?

If you are ready to purchase a car today, and you are confused about whether to buy one that runs on gasoline or one that runs on diesel, you have to consider a lot of things, and more specifically, how diesel cars function exactly.

Diesel cars have been proven over time to be more efficient, stronger, and more durable than gasoline cars, however, asides from that, the only other major difference is the type of fuel they run on.

Diesel cars work with a compression-ignited injection system that requires diesel to work. As a result of this system, using gasoline on cars like this will not only degrade the performance but also completely degrade the engine.

On the other hand, cars that run on gasoline do that because they work with a spark-ignited system, using spark plugs that are ignited by gasoline.

There are many benefits diesel cars have over cars that run on gasoline, and you can as well say that, in all respect, diesel cars are better.

With diesel vehicles, you get more efficient engines. Their engines work harder, and faster and consume more than 30% less fuel than gasoline cars.

Another advantage diesel cars have over gasoline cars is that they don’t emit as much C0 as gasoline cars, and this is the reason why they use a different type of catalytic converter to control the emission system of cars.

And because of this, diesel cars are taxed lower than gasoline cars, as they don’t do as much damage to the environment as gasoline vehicles.

There are many more advantages, such as how their engines last for longer years, they are more powerful, they don’t succumb to wear and tear as gasoline cars do, and so on.

The one major disadvantage you might want to ascribe to diesel cars is that they are a lot more expensive to maintain, and diesel itself is a lot more expensive than gasoline.

Do Diesel Cars Have Catalytic Converters?

Yes, diesel cars also have catalytic converters, even though the catalytic converters in diesel cars are completely different from the ones in gasoline cars because they perform nearly different functions.

Diesel cars use compression-ignited systems for lighting up the diesel in the engine, and as a result, there is a very low emission of C0.

The way it works is, that compression-ignited systems require the use of more oxygen in the process of ignition, and so, the emission of toxic fumes that are controlled by catalytic converters is reduced.

Unlike in gasoline vehicles where spark plugs are used to ignite the fuel, and so, a lot of C02 is emitted from the process, requiring a strong catalytic converter in the emission system to override the toxins released.

The major function of catalytic converters in diesel vehicles is also to detox the little number of toxic fumes coming out of the engine and change the chemical components to make them nontoxic.

So, yes, diesel cars have catalytic converters. Although they are not as strong or have as many precious metals as gasoline vehicles because they don’t have to deal with a lot of toxic fumes, they are still there, and they function as fume component transformers.

Functions of Catalytic Converters on Diesel Cars

As earlier said, catalytic converters in diesel cars don’t work as they do in gasoline cars, but they still have their functions, and they help the car run smoother, and the environment a lot better.

Here are the functions of catalytic converters on diesel cars:

1. Conversion of Toxic Elements

This is the major purpose of catalytic converters in diesel cars. They convert toxic elements such as particulate matter, carbon monoxide, and hydrocarbons to nitrogen, carbon dioxide, and water.

They do this so efficiently, that the toxins in the fumes are more than 90% eradicated before they are released into the environment. This is why it is important to have your catalytic converter replaced when stolen.

2. They Operate as Diesel Oxidation Catalysts

This is particular to diesel vehicles. They operate as a diesel oxidation catalyst since diesel vehicles use a lot of oxygen.

3. Helpful for Engine’s Emission System

Without catalytic converters, the emission system of a diesel vehicle will break down sooner than it would have with catalytic converters. Therefore, they are helpful for diesel vehicles engine.

4. They Help Diesel Cars Become More Environment Friendly

With the catalytic converter, the toxic emissions from diesel cars are very limited, and even in some cases, completely eradicated.

Can a Catalytic Converter be Stolen from a Diesel Engine?

Yes, catalytic converter can be stolen from a diesel engine but this is not likely to happen, because the catalytic converter of diesel engines is worthless to thieves. They don’t have the precious metals that are the real target for catalytic converter thieves.

Gasoline vehicles are more susceptible to catalytic converter theft than diesel engines because they have a lot more precious metals than diesel engines.

What Happens if a Catalytic Converter is Stolen from Diesel Cars?

When a catalytic converter is stolen from a diesel car, the car loses its ability to transform the little toxic matter that emits from the engine into environment-friendly fumes and thus contributes to bad environmental conditions.

Also, acceleration becomes slower in diesel engine cars, as well as the overall performance of the car begins to dwindle.

The vehicle begins to make weird noises and develop a terrible smell that affects the driver as well as the environment.

All around, the driving experience of a diesel vehicle, when the catalytic converter is stolen becomes terrible. Diesel cars and all cars generally are better with catalytic converters.

How Long Does Catalytic Converter Last on Diesel?

A catalytic converter lasts for as long as 100,000 miles, or even around ten years on diesel vehicles, however, this depends on the overall condition of the vehicle and the condition in which you are driving the vehicle.

The more frequently you go on trips, the higher the chances of the catalytic converter wearing out. However, generally, diesel catalytic converters last for ten years, give or take.

When Did They Start Putting Catalytic Converters on Diesel Cars?

While catalytic converters became required for gasoline cars in 1975, it didn’t take until a little over fifteen years before catalytic converters started featuring in diesel vehicles.

Diesel cars started getting catalytic converters starting from 1994, exactly 19 years after they started putting catalytic converters in gasoline cars.

How to Protect Your Diesel Car Catalytic Converter from Thieves

Although diesel cars’ catalytic converters don’t get stolen often, as they don’t have as much worth as gasoline converters, it doesn’t mean you still can’t take extra measures to protect your catalytic converters from thieves.

Ensure that you park your diesel car in well-lit parks, ensure that where you park your car is not secluded from the public, and everyone can see what is happening.

Another tip is to park directly across CCTV cameras and ensure you aren’t parking in a blind spot, so thieves will get caught on camera and be identified easily.

You can also brand your catalytic converter with paint or scratches that you will recognize and can be identified with you, such as your name or plate numbers.

Finally, you might consider getting a security system for your vehicle to protect parts of your car from thieves.


Diesel cars have catalytic converters, but they don’t worth as much as the catalytic converter in gasoline vehicles, so they are least likely to be stolen.

However, you should take measures to protect your catalytic converters from thieves by not parking in reckless places, and doing your due diligence for security purposes.