Is nitrogen-enriched gasoline good for my car?

Will a special "nitrogen-enriched" gasoline formula keep your car's engine cleaner? Gas company Shell thinks so, and it's launched a big campaign advertising their new gas. See more pictures of car engines.
Justin Sullivan/­Getty Images



When you're looki­ng to fill up your car with gas, how much thought do you really put into the process? Do you simply pull into the nearest gas station, or do you shop around a little, looking for the cheapest gas available? If you have your car's engine in mind, do you think about which type of gas will work best in your vehicle? In fact, a consumer and retail market research company, NPD Group, has identified two camps of gasoline seekers: those who look for the lowest prices out there and those who want better performance from their fuel [source: Greenberg].

All gas stations have to distribute gasoline that includes additives designed to clean important engine parts -- the Environmental Protection Agency (EPA) requires it. But if you've watched television or driven by a Shell gas station recently, you may have noticed advertisements for a special kind of gasoline with a fancy, vaguely scientific name: Shell Nitrogen Enriched Gasoline. In March 2009, the Shell gas company began pumping this gasoline at its stations and emphasized the fuel's formidable cleaning power.

­As fuel prices continue to jump around only to settle back down unexpectedly, many drivers are looking for more efficient ways to use and conserve fuel. There are several driving habits people can alter or improve, including paying attention to local speed limits and avoiding hard braking and rapid acceleration. But taking care of your car's engine is important, too. The performance of your vehicle's engine is a big factor in fuel economy. A properly maintained, well-cared-for engine will give you better fuel efficiency, and therefore you'll spend less time watching the prices tick away at the pump. The types of gas you use can affect your engine, too, and Shell would like you to think that its particular blend of gasoline will affect your engine positively.

So, how does Shell's nitrogen-enriched gas work in a car's engine? Does Shell's gas really perform better than other types of gasoline, or are they simply jumping onto the efficiency bandwagon with a gimmicky advertising campaign? Keep reading to find out.

Nitrogen-enriched Gasoline and Engine Gunk

These valves are clean, but after a while carbon deposits can build on them and create problems for your engine. Shell's Nitrogen Enriched Gasoline attempts to solve the problem of gunk.
These valves are clean, but after a while carbon deposits can build on them and create problems for your engine. Shell's Nitrogen Enriched Gasoline attempts to solve the problem of gunk.


­A ­gasoline engine generates power through internal combustion. During this process, a series of pistons compress and ignite a mixture of air and a high-energy fuel (like gasoline) in a very small space, creating the energy necessary to move your car forward.

We'll talk in very general terms here, but the amount of gasoline and air that ignites within your engine determines how much power your engine produces. A set of valves help regulate how much of the air and fuel mixture is allowed to enter the combustion chamber at the top of each cylinder. These valves act like small manhole covers that open and close at precisely the right times to allow the engine to cycle properly. Here's how it happens: One set of valves opens to allow the air and fuel mixture to flow into the combustion chamber, then the chamber is sealed while the volatile mixture is compressed and ignited. The final step is when a second set of valves opens to release the exhaust gasses from the chamber and then the whole process begins again. A rotating camshaft applies pressure to each valve when it's time to let fuel in and also when it's time to let the exhaust out. So, when you step on your gas pedal, you're technically controlling how much air and fuel those valves will let in. The valves, as you'll see, are an important part of your car's engine, and they're performance is integral to the overall performance of your car.

A major byproduct of combustion is carbon deposit build-up, or what Shell has hereby dubbed in their ad campaign "gunk." Gunk is essentially what it sounds like -- it's black soot that can harden on the cylinders, pistons and valves of an engine. If too much collects, this gunk can negatively affect engine performance, causing your car to burn more oil, overheat and even burn gasoline less efficiently. Valves inside an engine are designed to let in a specific amount of air and fuel, and when this process is interrupted by carbon deposit build-up, your car won't be performing up to its potential.

So what does Shell's nitrogen-enriched gasoline have to do with this? The nitrogen formula in this specific type of gas functions as a detergent. Special detergents or additives are added to fuels to help clean engines. When Shell's nitrogen-enriched gasoline runs through your engine, it passes over and comes into contact with the system's valves. Shell claims that nitrogen-enriched molecules chemically react with carbon deposits that have collected on the valves. These nitrogen-enriched molecules then clean the valves and permit maximum gasoline and air compression within the cylinder.

So, is Shell's nitrogen-enriched gasoline a big deal? Is it really something to get excited about? Shell certainly seems to think so. Read the next page to find out why.

Fuel Quality vs. Alternative Fuel

Shell's decision to back away from alternative fuel research may explain why the company wants to push its fuel quality.
Shell's decision to back away from alternative fuel research may explain why the company wants to push its fuel quality.
AP Photo/Reed Saxon


When Shell launche­d its advertising campaign pushing the new fuel, a series of commercials ran on several major channels, including MSNBC, Oxygen, USA, A&E, the Discovery Channel, ESPN, Speed and the Golf Channel. These ads, part of what Shell dubbed the "Passionate Experts" campaign, featured goofy, somewhat aloof scientists promoting the nitrogen-enriched fuel.

Shell's Web site has its own section dedicated to its nitrogen-enriched gasoline. The home page acts as a main lobby, with doors to rooms like the "Laboratory," the "Garage," the "Test Bay" and the "Lounge." You can click on any of these doors as you explore some information on Shell's product, but there's just as much cross-promotional material available as educational substance, if not more. For instance, banners for NASCAR events take you away from the page, and offers for Shell's frequent member card show up in strategic locations. And repeating animations of those silly scientists are there, too, trading secret handshakes, playing rock-paper-scissors and generally being inane.

Shell's engine-cleaning gas isn't technically anything new, either, since all gasoline products have been required by the EPA to include a minimum amount of additives and detergents [source: U.S. Environmental Protection Agency]. However, Shell's gasoline does meet and exceed TOP TIER Gasoline Detergent standards, which is a voluntary standard that several major automakers including Audi, BMW, General Motors, Honda, Toyota and Volkswagen created in order to improve the quality of gasoline.

But the most revealing reason behind Shell's efforts to push nitrogen-enriched gas might be its decision to suspend research on alternative fuels. In March 2009, Shell announced it would hold back indefinitely on funding and research for solar and wind power. Hydrogen power was given the boot, too. Analysts cited recent drops in oil prices and an economic downturn as possible reasons for the move [source: Hadhazy].

For more information about fuel and other related topics, follow the links on the next page.

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More Great Links


  • Greenberg, Karl. "Shell Campaign Lauds 'Nitrogen-Enriched' Gas." MediaPost Publications. March 2, 2009. (March 30, 2009)
  • Hadhazy, Adam. "Shell oil company bails on most alternative energy research." Scientific American. March 20, 2009. (March 30, 2009) ?id=shell-oil-company-bails-on-most-alt-2009-03-20
  • Reuters. "Shell Rolls Out All-New Shell Nitrogen Enriched Gasolines With Free Fill-Ups." March 6, 2009. (March 30, 2009)
  • Shell. "Gunk-Free Answers." (March 30, 2009) gunk_free_nation/live_gunk_free/faqs.html
  • U.S. Environmental Protection Agency. "Gasoline Detergent Additives Enforcement and Recordkeeping Requirements." July 16, 2008. (April 6, 2009)