What happens if you use the wrong fuel?

In some cases, using the wrong fuel is harmless. Other times, like if you accidentally put E85 fuel in a car that's not designed for it, you can void your engine warranty or cause costly damage to fuel lines. The price to fix a car from a fueling mishap can be steep, but there's no reason to panic. If you put the wrong fuel in your car, get it towed to a mechanic where they will drain it out and make sure it's running smoothly.

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Mistakes involving diesel fuel

Whether putting diesel in a gas car or pumping standard gasoline into a vehicle with a diesel engine, drivers often mix up these two fuel types. Here's what happens in both situations:

  • Putting diesel in a gas car can clog your fuel filters and fuel injectors, making your vehicle suddenly inoperable. This is because diesel fuel is thicker than regular gas, which causes it to gum up your car's internal systems quickly.
  • Putting gas in a diesel vehicle can also have a serious impact on your engine. Gasoline is thinner than diesel, so it ignites faster. The resulting heat can easily damage the engine's fuel sensors, resulting in costly repairs.

What to do if you use the wrong gasoline

Once you've recognized the mistake, stop your car immediately to avoid additional damage. Then, it's a good idea to call for a tow and to get your system flushed by a trusted auto technician. In both cases, your fuel tank will need to be drained, and your fuel lines will require a thorough cleaning.

Mistakes involving E85 ethanol

Many newer flex-fuel vehicles are specifically designed for E85 ethanol fuel. This fuel's chemical make-up is derived mostly from biomass materials such as corn. If you accidentally put E85 fuel in a car built for regular petroleum-based gasoline, chances are your check engine light will come on. And while that's never a good feeling, a one-time mistake shouldn't cause engine damage. Still, you should consult a trusted mechanic to make sure your vehicle won't develop any issues.

Much greater risks occur when E85 is used in a non-flex-fuel vehicle over time. Continually filling a standard gasoline car with this high-ethanol fuel can result in serious fuel system corrosion. Plus, when you accidentally put E85 fuel in a car, it may void your engine warranty. That means you could be on the hook for the repairs, even if your car is brand new.

Does insurance cover gasoline removal?

Your auto insurance most likely won't cover the costs of removing and flushing the wrong fuel from your vehicle. But it's always a good idea to check with your insurer to find out for sure.

If you're wondering what to do if the gas station pumps the wrong gas into your car, you may want to consult a legal professional. If your vehicle suffered serious damage due to the gas station's mistake, you might be able to sue for damages to recoup any repair and towing costs.

Don't let fuel accidents happen to you

Of course, the easiest way to avoid engine damage and other inconveniences relating to accidental fueling is to prevent it from happening in the first place. Always make sure you know the specific grade and fuel type for your vehicle. And remain focused and alert when filling up. Remember: If the nozzle doesn't fit perfectly into your tank, it's probably not the right fuel.

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