Fuel Additives: What Are They & Do They Work?

What Are Fuel Additives?

There are two primary types of fuel additives: fuel performance enhancers and fuel stabilizers. Fuel additives for performance are intended to improve the capabilities of your vehicle’s engine while it is running or in use. Fuel stabilizers are designed to keep fuel in a functional condition when being stored for a long period of time without use. It is fuel performance enhancers that most people think of when discussing fuel or gasoline additives.

Are Fuel Additives Worth the Money?

Fuel or gasoline additives often make impressive claims about how they will improve the performance of your engine, such as “improves fuel economy by 20 percent.” That’s a pretty enticing claim, and one you might read on a bottle of fuel additive, says the Federal Trade Commission. It’s easy to see the appeal—spend a few bucks, dump the product into your gas tank, and make that money back with the gas you’ll save. But is there validity to the claim that fuel additives are worth investing in for your vehicle?

Adding to the complexity of the question is that “fuel savers” are just one type of additive, which we’ve all seen lining the shelves of gas stations and auto shops. Others exist to do things like clean fuel systems and injectors. “They make additives for everything,” says Jill Trotta, director of the automotive group at RepairPal.

But our fuel today already comes with lots of additives, which have been used in gasoline since the 1920s. Do our cars really need the additional help? The short answer: It depends. Here’s Trotta’s advice on some types of additives.

Types of Fuel Additives

Fuel System Cleaners

The most common form of additive, fuel system cleaners claim to scrub carbon and other buildup from your fuel system—something Trotta says they do quite well—which can help your car’s overall performance. They’re also sometimes advertised as fighters of fuel system corrosion—a problem that some say can occur in certain cars that use fuel with a high enough level of ethanol. But Trotta dismisses this claim, saying that such rust buildup is quite rare. “It would have to be an extraordinary circumstance for that to happen,” she says.

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Fuel Injection Cleaners

A specific type of fuel system cleaner, fuel injection cleaners scrub away carbon that has built up on the fuel injectors, which can negatively impact gas mileage. This is a problem particularly common in certain cars with higher-end engines, whose overhead cam set-up can lead to more carbon accumulation. “Some models of cars build up carbon,” says Trotta. “If you don’t drive a lot on the highway, if you’re doing a lot of short trips and the engine doesn’t get hot enough to clean itself, you might want a fuel injection cleaning.”

Gas Mileage Additives

Beyond simply cleaning your fuel system, additives can promise all sorts of benefits for your engine. Additives that promise to increase gas mileage are a popular product, especially of course when gas prices rise. But the FTC’s site recommends a buyer-beware approach. “It’s a smart idea to be skeptical of any gas-saving claims for automotive devices or oil and gas additives,” says its website. Trotta agrees. “If it does make any difference,” she says, “it’s going to be minimal.”

Cooling System Additives

While most fuel additives are, at worst, harmless, Trotta warns against using engine cooling system additives that claim to plug leaks. These, she says, will only work temporarily on small leaks, will have no effect on larger leaks and could cause damage to your car’s mechanics. When you see coolant collecting on the floor of your garage, she says, you’re better off calling your mechanic than reaching for a bottle of cooling system additive.

The Bottom Line On Fuel Additives

If you’re interested in using an additive, Trotta recommends finding a mechanic you can trust and following the maintenance calendar laid out in your owner’s manual. “The people that manufacture the vehicle generally know what’s best for it,” she says.

A good mechanic can protect your engine, but it takes great auto insurance to protect your whole car. Get a free quote from GEICO today.

Next article: 6 Hacks to Help You Save on Gas

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    Leave a comment

  1. Isabella Mason says,

    Jaguar does not honor their warranty. I had to have my turbocharger replaced on my diesel truck about a year ago. My regular mechanic was doing a routine check and found the turbine blades were breaking apart. The mechanic is someone that I have trusted for 10 years so called Jaguar concerning the warranty. Basically, without even requesting for the turbocharger to be sent to them for future investigation, is blaming the damage on everything except the turbo. According to my mechanic there is no other reason for the turbo charger damage is that Jasper did a very poor rebuild and sold a faulty part. I don’t drive this vehicle much so there is maybe 600 miles on this “new” faulty turbocharger.

  2. Richard Roberts says,

    Great information for people who are not mechanically inclined. ? I regularly have my car maintained to avoid undue wear and damage or even a break-down.

  3. John says,

    Good read,in my younger days I added gas tank cleaner of some kind hoping it would do what it claimed to do.These days, I’m 72 I get brakes checked the engine tuned the transmission fluid changed the radiator flushed and the timing belt checked and the tires rotated.
    I own a 2004 Saturn View, I have the work mentioned above every few years and keep my eyes on the mileage.

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