How To Reduce Emissions From Diesel Engines


Diesel engines convert fuel energy into mechanical power. Because diesel fuel is a combination of hydrocarbons, the ideal combustion process produces only carbon dioxide and water vapor. Therefore, diesel engines emit less carbon dioxide and greenhouse gases than gasoline engines, making them more fuel-efficient. 

However, diesel engines release 25 to 400 times more particulate black carbon and organic matter, like soot, per mile. It’s important to maintain diesel engines by finding ways to reduce their emissions. It’s good that there are many ways to accomplish this goal with the advancement of technology. Read on below to find out more. 

1. Installing Diesel Particulate Filter  

Diesel Particulate Filter (DPF) catches exhaust soot, which can help reduce emissions from diesel engines. This specialized filter traps the soot. That’s why the filter must be cleaned and emptied regularly to work efficiently.

It’s crucial to understand the role of diesel catalytic converter (DOC) in diesel engine emissions when tackling DPF. DOC is a part of a diesel engine’s emission system where the engine exhaust enters. It protects the engine exhaust from pollutants, breaking them into less harmful substances. 

However, untreated diesel engine exhaust has harmful chemicals, such as organic particulates, hydrocarbons (HC), and carbon monoxide (CO). The DOC converts them into natural and less harmful components, including water (H2O) and carbon dioxide (CO2), by incorporating oxygen.

As a result, the diesel engine’s exhaust generates less pollution. Click to learn more here about DPF DOC. 

2. Using Diesel Fuel Additives 

Diesel fuel additives provide several benefits to diesel engines. They remove harmful deposits from the vehicle’s fuel system, thereby reducing emissions.

Emissions are more controllable in diesel engines using additives. It involves using a renewable or oxygenated fuel, such as ethanol and methanol, with diesel fuel.

In addition, incorporating additives into fuel tanks can help increase lubrication, improve a car’s old weather performance, and increase fuel stability. Fuel additives can protect and enhance a diesel engine’s efficiency at a relatively minimal cost.

3. Changing Engine Oil Regularly 

Keeping your diesel engine in its pristine condition through regular car servicing can help reduce emissions. Don’t miss this important and practical step, whether you have a diesel-powered pick-up truck or a sports utility vehicle (SUV). 

Changing engine oil reduces your diesel car’s emissions because fresh engine oil cleans, lubricates, and cools the engine. Engine oil prevents engine wear, and regularly changing the oil keeps the engine running efficiently.

Generally, replacing diesel engine oil and filter must be at 7500 miles or every 400 work hours or every six months. The frequency between replacements may increase depending on the quality and type of engine oil.

4. Embracing Fuel Injection Technology 

Diesel fuel injection systems can help reduce emissions. They help reduce combustion noise, improve fuel economy, and ensure future emission standards compliance. There are different fuel injection strategies that auto mechanics employ to attain these goals. 

For instance, the increase in fuel injection pressure helps improve the combustion process and fuel atomization. It results in higher brake thermal efficiency and generates fewer hydrocarbons, carbon monoxide, and particulate matter emissions. 

On the other hand, pilot injection helps reduce combustion noise and nitrogen oxide (NOx) emissions. Immediate post-injection helps oxidize soot, while late post-injection helps regenerate the diesel particulate filter. All of these mechanisms can significantly reduce emissions from diesel engines. 

5. Improving Exhaust Gas Recirculation 

Exhaust Gas Recirculation (EGR) refers to an emission control technology or widely accepted techniques to help reduce significant NOx emissions. This technology is suitable for most diesel engine types, including light-duty, medium-duty, and heavy-duty engines. 

EGR coolers improve a diesel vehicle’s performance. It cools the exhaust gas and recirculates it into the intake manifold. Cooled exhaust gas helps reduce the peak combustion temperature, decreasing the amount of NOx. 

Moreover, the EGR cooler works with the EGR valve, creating a combination of air, exhaust, and fuel gases to reduce emissions. 

Air mass sensors regulate diesel engines’ exhaust gas recirculation. It precisely measures the mass of the recirculated exhaust gas. In diesel engines, air mass sensors also control exhaust gas recirculation. 

A complete air mass sensor has a flow passage where the intake air passes past the sensor unit. This component is essential in air supply and exhaust gas reduction. Hence, a contaminated or malfunctioning air mass sensor can cause incorrect input signals, affecting other components. This air mass sensor issue can lead to other problems, such as a lack of power and black smoke. 

Improving EGR by cleaning dirty air mass sensors or replacing them due to electrical or mechanical failure is advisable. 


Reducing the emissions from diesel engines can help protect public health and the environment. Practical solutions include regular car maintenance and adding additives. Advanced technological solutions include the use of DPF and fuel injection technology. If you’re in doubt about the best way to reduce your diesel engine’s emission, consult a professional today.

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