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How to Reduce Diesel Exhaust Build Up

How to Reduce Diesel Exhaust Build Up

Diesel fuel is an amazingly efficient energy source and is used worldwide for transportation. Trucks, cars, trains, ships and heavy equipment all benefit from the dependable power supplied by diesel engines. It is an elegantly simple ignition process housed inside a diesel engine. Take air, inject a bit of diesel fuel and compress it until self-ignition occurs. Note that the exhaust coming from a diesel engine is different from what comes out of a gasoline engine tail pipe. Let’s take a look at what exactly is diesel exhaust and how to reduce diesel emissions.

Why Is Diesel Exhaust Different From Gasoline Exhaust?

Yes, diesel exhaust smells different, but the diesel engine combustion process actually changes what kind of gasses and byproducts exit the combustion chamber. Conditions inside a diesel engine combustion chamber involve higher temperatures and higher cylinder pressures than a gasoline engine. Both gasoline and diesel engine exhaust include nitrogen, carbon dioxide and water vapor. However, diesel exhaust includes higher concentrations of particulate matter and higher levels of nitrogen oxides (NOx). 

What Is the Problem With Diesel Exhaust?

Diesel engine combustion creates extremely fine soot, which is a byproduct of not enough air during combustion. These tiny particles become airborne and end up in the atmosphere we all breathe. This soot can trigger asthma attacks and irritate the lungs plus is even linked to lung cancer. Chemicals from diesel exhaust, like nitrogen oxides (NOx), contribute to the formation of ozone, which is harmful when it settles at the ground level and can cause breathing issues. These issues and others are the reason why there is a push for a diesel emission reduction through various programs. 

What Causes Diesel Soot?

If you want to know how to reduce black smoke from diesel engines, you need to reduce the causes of diesel soot. The root cause of diesel soot is incomplete combustion. Unburned fuel from insufficient air or an oversupply of fuel will cause a diesel engine to emit the familiar black smoke. When a truck “rolls coal,” it is actually dumping large amounts of fuel into the engine, which does not get burned and is merely expelled through the exhaust.

How to Reduce Diesel Exhaust Buildup

The buildup inside a diesel exhaust comes from carbon-based soot. A sooty exhaust buildup is expected from any engine as time passes. But also, if your diesel engine isn’t running efficiently, the result is more carbon buildup. Many newer diesel-powered vehicles come fitted with a diesel particulate filter (DPF), which captures most of the soot before it exits the exhaust pipe. Eventually, the DPF will reach a point where it needs renewed. Rather than removing and replacing the DPF often, the captured soot is burned under extreme heat inside the DPF unit. The resulting ash stays inside the DPF until it is cleaned based on the manufacturer’s specified service schedule.

How Does DEF Work?DEF container

Amazingly, urea in diesel exhaust fluid (DEF) can transform some nasty exhaust emissions into far less noxious materials. So, how does urea reduce diesel emissions? DEF is injected into the exhaust system after the diesel particulate filter. Nitrogen oxides (NOx) react with urea to create nitrogen gas and water vapor. The resulting mixture is then carried out of the exhaust pipe carrying far less noxious components than if it were untreated.

If you are wondering how to use blue DEF diesel exhaust fluid, luckily, the answer is very easy. Modern diesel fuel-powered vehicles typically have a DEF filler port near the fuel filler door. Your vehicle should alert you when it is running low on the fluid. When that warning occurs, just refill the DEF tank with the amount specified in your owner’s manual. That’s it! Your vehicle handles every other aspect of the DEF usage cycle. Based on your driving, the onboard computer decides how much to use and when. For now, DEF is the best diesel emissions reducer in use. Luckily, brands like Blue DEF fluid are widely available from your local NAPA Auto Parts store.

Taking a Look at Large Scale Diesel Exhaust Reduction Efforts

Cleaning up modern diesel emissions started with the Energy Policy Act of 2005. Inside this law was the first outline of the Diesel Emissions Reduction Act, which received its own law in 2010. The goal was to use tax funds to help reduce diesel emissions via methods such as retrofitting emissions systems and repowering older vehicles with modern, cleaner engines. In some cases, such as with school buses, an all-electric bus could replace an old diesel bus altogether. Funding got allocated through Diesel Emissions Reduction Act grants.

Another tactic to clean up diesel exhaust was taken back in 2006 when a new kind of ultra-low-sulfur diesel fuel was mandated across North America and most of Europe. This new diesel fuel formulation has a far lower percentage of sulfur than the previous formulation. Using ultra-low-sulfur diesel combined with modern emissions controls can drastically lower soot and harmful exhaust gasses. But this also means that the 2007 year and model and newer diesel-powered vehicles must only fuel up with ultra-low-sulfur diesel or risk damage to onboard emissions equipment.

Doing Your Part

Do you drive a diesel-powered vehicle and want to learn how to reduce NOx emissions in diesel engines? It’s simple: keep your vehicle maintained to the manufacturer’s specifications. And keep the DEF tank filled so you don’t end up in reduced power mode accidentally. If the check engine light comes on, grab an OBD scanner and find out the cause.

Looking to pick up some Blue DEF diesel exhaust fluid for your Ford F350 SuperDuty? Head to your local NAPA Auto Parts store or order online at NAPAonline. If you are in a hurry, you can choose Buy Online, Pickup in Store. You can also sign up for NAPA Rewards and start earning Points toward future purchase discounts. For every $1 you spend online or at a participating store, you will earn 1 Point. Once you earn 100 Points, you get $5 off your next purchase automatically!

Photo courtesy of pxfuel.

Brian Medford View All

With an automotive writing career spanning over two decades, Brian has a passion for sharing the automotive lifestyle. An avid DIYer he can usually be found working on one of his many project cars. His current collection includes a 1969 Olds Delta 88 convertible, BMW E46 sedan, and a slant-6 powered 1975 Plymouth Duster.

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