It is a question that comes up more often than you might expect: can you put aviation fuel in a car? The short answer is technically yes, but practically no. And if you are thinking about it, there are some important things you need to know before you pull up to an airport fuel pump.
What Is Aviation Fuel?
Aviation fuel comes in two main types. Avgas (aviation gasoline) is used in piston-engine aircraft — the smaller planes you see at regional airports. Jet fuel (Jet-A) is a kerosene-based fuel used in turbine engines — the kind that powers commercial airliners.
When people ask about putting aviation fuel in a car, they are almost always talking about avgas, specifically 100LL. The “100” refers to its octane rating and “LL” stands for low lead — though low is relative. More on that in a moment.
Why Would Anyone Want to Use Aviation Fuel in a Car?
The appeal makes some sense on the surface. Avgas 100LL has a very high octane rating — roughly equivalent to 105 octane by automotive standards. It contains no ethanol, which some performance and classic car enthusiasts prefer. It is also highly refined and stable, with a much longer shelf life than pump gasoline.
For old-school hot rodders and racers, avgas was once a go-to performance fuel before purpose-built racing fuels became widely available. Some people still use it in lawnmowers, generators, and old farm equipment without issue.
Why You Should Not Put Aviation Fuel in a Car
Here is where it gets complicated. While putting aviation fuel in a car will not cause an explosion, it will cause a number of serious problems for most modern vehicles.
Lead content. Even the low-lead version of avgas contains about 1.9 grams of lead per gallon. Lead is incompatible with the oxygen sensors, catalytic converters, and other emissions equipment found in virtually every car built since the 1970s. Putting aviation fuel in a car with a catalytic converter will destroy it quickly. Spark plugs will foul. Sensors will fail.
It is illegal for road use. Avgas is not taxed for road use. Using it in a car on public roads is a federal violation in the United States. Beyond the tax issue, using leaded fuel on public roads is prohibited under the Clean Air Act.
It is not optimized for automotive engines. Despite the high octane number, avgas is formulated for piston aircraft engines that run at low RPM and high torque for extended periods. Automotive engines operate very differently — higher RPM, constant throttle changes, stop-and-go use. The fuel characteristics that make avgas good for a Cessna do not translate well to a car engine.
Access is not easy. You cannot pull up to an airport fuel pump in your car. Avgas is dispensed airside at airports, meaning you would need special access. It is also more expensive than pump gasoline.
What About Jet Fuel in a Car?
Jet fuel (Jet-A) is a different story entirely. It is a kerosene-based fuel and will not work in a gasoline engine at all — the engine simply will not run on it. In a diesel engine, Jet-A can work in a pinch since it is chemically similar to diesel, and the US military has operated diesel vehicles on jet fuel for decades. But it is not recommended for civilian use and can cause long-term wear on fuel system components designed for diesel.
When Aviation Fuel in a Car Might Be Acceptable
There are narrow situations where using avgas makes sense. Vintage vehicles with no catalytic converter, running without oxygen sensors, and never driven on public roads — think track-only race cars or show vehicles — can tolerate avgas. Some classic car owners in regions where ethanol-free gasoline is hard to find have used avgas as a workaround, accepting the trade-offs.
But for any modern vehicle used on public roads, putting aviation fuel in a car is a bad idea legally, mechanically, and financially.
The Bottom Line
Can you put aviation fuel in a car? Technically, the engine will run. Practically, you will damage your catalytic converter, foul your sensors, foul your spark plugs, and potentially face legal consequences. If you are chasing higher octane fuel, look for ethanol-free premium gasoline or purpose-built race fuel instead. Both are legal, widely available, and designed for automotive engines.
Aviation fuel belongs in aircraft. Leave it there.
FAA Avgas Information: https://www.faa.gov/aircraft/air_cert/design_approvals/piston_avgas
Sunoco Fuel Facts: https://www.sunoco.com/fuel-facts/post/why-not-avgas