What Is Fuel Stabilizer & Is It Necessary For Your Engine?

One thing you swiftly learn throughout your car ownership career is that gasoline isn't the only liquid you need to put in there. A car plays home to a variety of fluids, from motor oil to the cleaning solution that shoots out of your windshield wipers. That said, most of these fluids serve some kind of obvious purpose, and their usage is generally considered baseline information. There are exceptions to this, however.

One particular kind of automotive fluid you may not have learned about in Driver's Ed is fuel stabilizer. The name sounds kind of futuristic, like something that would need to go in a rocket ship, which may imply that it's a fancy, extraneous element that your car doesn't actually need. Whether your car's engine needs or doesn't need a fuel stabilizer, though, depends heavily on several factors, some of which may be more relevant to certain kinds of drivers in certain kinds of driving situations.

The thing about gasoline is that, even if you're not actively driving your car, it gradually starts to evaporate and go stale if you leave it for too long. This both forms gross, sticky residues on the carburetor and generally makes the gas less effective at powering the engine. The purpose of a fuel stabilizer is to inhibit this expiration process and help an idle tank of gas last longer than it normally would.

Fuel stabilizer is a chemical solution, often a petroleum-based one, that's added to your car's fuel tank alongside regular gasoline. Utilizing a combination of lubricating and antioxidizing agents, the fuel stabilizer prevents the gasoline in the tank from evaporating or going stale, which in turn keeps it road-ready for longer stretches of time. Many fuel stabilizers also contain protective elements that, when flowing through the engine, leave a protective coating behind. This helps to protect the internals of the engine against ambient water and corrosion.

In the vast majority of driving situations, a fuel stabilizer is not a required component for regular engine operation. Assuming you're driving your car on a regular or semi-regular basis, you don't really need to worry about your gas evaporating or going stale before you can use it. While a fuel stabilizer won't hurt your engine, adding it to the gas tank is an extra chore that isn't really necessary.

As fuel stabilizer mixes with the gasoline in your tank to do its job, if you wanted to keep using it, you would need to add in the fuel stabilizer every single time you visit the gas station to get the fuel topped off. Additionally, since fuel stabilizer is meant to be added to a nearly-empty tank, you would need to burn off your car's entire fuel reserves before going to the gas station every single time, which is both time and cost-ineffective, especially considering that you'd need to buy a standalone tank of stabilizer regularly to keep up with refueling.

The situations where you should be using a fuel stabilizer are when you own a vehicle that you don't drive very much, like a collector's car, or when you're putting a vehicle in storage for an extended period like during the winter season. Rather than with a regularly used car, the ideal scenario for a fuel stabilizer is keeping the gas fresh in a vehicle that's going to be sitting unused for a long time.

Normally, when you're storing a vehicle long-term, you're supposed to completely drain out the gas tank so you don't get any of that aforementioned evaporated crud on the internals. However, if you can't be bothered to do this, or otherwise plan on driving the vehicle sporadically, fuel stabilizer eliminates the need for tank draining by just preventing evaporation from occurring in the first place. Just keep in mind that different stabilizer brands have different shelf lives; many can keep a tank fresh for up to a year, but you should read the brand's directions just to be sure.