Why Your Garage Suddenly Smells Like Gas (And How To Fix It)

Garages are used for more than just storing vehicles these days. Some people turn them into a home gym or use it as a workshop, while others may just want the space for storage. If you are looking for ideas to make the garage a fun and functional room, you have to figure out a way to bring your plans to life while sharing the space with dirty, smelly items like lawn mowers and cars.

If your garage smells like gasoline, it may derail your ideas for using your garage as a room. It would be tough to focus on running on a treadmill when you're worried about breathing in toxic fumes.

So why does your garage suddenly smell like gasoline? The most likely culprit is a spill when filling up one of your pieces of outdoor power equipment. This is a common problem that happens in the garage, especially if steps are not taken to prevent spills when putting gas in your lawn mower, trimmer, or other machinery. You should use a funnel to prevent spills, while also pouring slowly to reduce the risk of overfilling the machine's tank. Unfortunately, even if you're careful, you might have a bad funnel or an awkwardly placed gas tank on the mower, leading to spills. Not all gasoline odors in a garage occur because of human error and fuel spills, though. Learn more about other causes of gasoline odors in the garage and how you can make them go away.

If you know you did not spill any fuel, but you still smell gasoline, inspect all the items in the garage that have gas tanks. It could be a leaking fuel tank from a lawn mower, snowblower, or a motor vehicle. Or perhaps you hit a rock while mowing that punctured your gas tank. Any plastic tank may develop a small crack or a slow leak that is causing the odor. 

Check the integrity of your gas can, looking for a crack or a loose seal. You may also want to inspect the gas caps on the fuel tanks for the machines stored in the garage. A loose cap allows fumes and vapors to escape, creating a constant odor. A similar problem may occur if you have a crack or leak in the fuel supply line with a mower, snowblower, or motor vehicle. If you have this problem, you may notice a little puddle of gasoline on the garage floor. If the leak is small, you might smell vapor instead of seeing a spot.

Another reason your garage may smell like gasoline is that you forgot to remove the fuel from your machine before you put it in storage. Old gasoline goes bad and emits a much stronger odor than fresh fuel. There may be a sour smell that you'll notice (and may linger) as soon as you remove the cap. Gasoline starts to degrade after three to six months of sitting idle.

The first step to resolving the odor is identifying the source. If you see a rainbow-colored puddle of gasoline in the garage from a spill or fuel line leak, take immediate steps to clean it up. You can use odor-absorbing substances such as charcoal, baking soda, coffee grounds, or cat litter on the area. After absorbing the liquid, you might need to clean any remaining fuel residue from the porous concrete, especially if you see a stain. While gas may evaporate off the concrete, it could still leave a stain behind. Warm water and a few drops of dish soap mopped over the stain can help but be sure to rinse with clean water afterward.

If you want to keep odors out of your garage, fill your mower or snowblower with gasoline outdoors because of the risk of spills. Do not store a gas-powered lawn mower vertically unless you drain the gasoline and oil beforehand. These liquids may leak when the machine is kept in this position but check your mower's manual for proper storage instructions. 

If the odor persists after you fix the problem that caused it, improve the ventilation in the garage. Open the doors and windows in the garage to increase airflow. Some people may even want to install a ventilation system to thoroughly remove the odor. This is especially true if you plan to use the garage as another living area.