Driving with the gas light on can be dangerous—for you and your vehicle. Here's how many miles you can actually drive on empty.
How Many Miles You Can Drive After the Gas Light Comes On
Do you like to live on the edge? We’ve all taken a bit of a gamble after the gas light comes on, guesstimating our available gas mileage and pushing our tank to the limit. Whether you were trying to beat rush hour or save money on gas by waiting to fill up, it can be a panic-filled moment looking for the nearest gas station. But just how many miles can you drive on empty? “The exact number will depend on several factors, including the type of car, how you drive, weather, traffic and driving conditions, and the fuel efficiency of the vehicle you’re driving,” says Chaya Milchtein, automotive educator and author of Mechanic Shop Femme’s Guide to Car Ownership.
But here’s the good news: You have more wiggle room than you think. While knowing how to find cheap gas and understanding how to get better gas mileage can help you avoid running on empty, you can still learn a thing or two about driving with your gas light on and preventing any damage to your engine. Here’s how many miles you should be driving with the gas light on.
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How far can you drive after the gas light comes on?
There’s not a standard number of miles you can drive when the gas light comes on, says automotive electrician and road safety expert Robert Muñoz. “Typically, it will light up when the tank is below 10% to 15% of its capacity.” In general, after the gas light comes on, Muñoz says it’s safe to drive about 20 to 30 miles in a smaller vehicle or up to 50 miles in a larger vehicle.
Of course, that doesn’t mean you should test the limits. “It’s often not worth the risk,” says Milchtein.
Does a car’s make or model affect how many miles after empty you can drive?
Yes, the type of car you have makes a big difference. Fuel efficiency varies greatly by a vehicle’s type, age and condition. “A hybrid, for example, can go a lot further on a gallon of gas than a pickup truck,” says Milchtein.
Consider each car’s mpg: If a small city car with a 10-gallon gas tank gets about 40 mpg, it could probably make it 40 miles to the next gas station. Meanwhile, a Dodge Ram 1500, which gets around 30 mpg on the highway, could make it as far as 100 miles after the gas light comes on. Typically, when the gas light goes on, about two to four gallons are left in the tank.
Does vehicle age, condition and road condition impact how far you can drive after the gas light comes on?
“A newer vehicle typically has better fuel efficiency than an older vehicle,” says Milchtein. “Cars that aren’t well maintained may have far less fuel efficiency than advertised.” So, a poorly maintained vehicle that hasn’t received regular oil changes or scheduled maintenance will get a lower mpg, and therefore, it will run out of gas sooner when on empty. On the other hand, if a vehicle has been well maintained, its age shouldn’t impact fuel economy, so you should be able to stick with the general estimates.
Muñoz says that road conditions also have an impact. For example, winter driving mistakes could put you in danger. Cold weather significantly reduces a vehicle’s fuel economy, and if your gas light comes on when it is extremely cold, you should get to a gas station quickly.
And don’t discount driving conditions, such as traffic and topography, either. “Driving in traffic tends to use more fuel due to the stop-and-start nature of the driving,” explains Milchtein. “Driving in hilly areas can also reduce fuel efficiency.”
What happens when the gas light comes on?
When the fuel level sensor detects fuel below a specific point, your low fuel light will come on your dashboard to signal it’s time to fill up the tank. The fuel level sensor is typically triggered when 10 to 15% of the fuel remains in the tank, Milchtein says.
Is it bad to drive with the gas light on?
“Knowing how much longer you have before you run out of gas can help prevent you from not making it to the gas station in time, getting stranded on the side of a highway, damaging your fuel pump or worse, losing control of your vehicle due to loss of power,” says Milchtein.
Fuel pumps are lubricated and cooled with the fuel in the tank, explains ASE Certified Master technician Jim Garnand, owner of Hi-Tech Car Care and president of Neighborhood Automotive Repair Professionals NAPRO). As such, running on vapors will tax the system.
Over time, you risk a clogged fuel filter as your car begins pulling dirt and debris through its engine. You also risk engine misfires, warns Muñoz. In an emergency, it is OK to drive a few miles with the gas light on, every once in a while, but generally, Muñoz believes the risk to your vehicle (and yourself if an accident were to occur) simply isn’t worth it.
Can driving with the gas light on damage your car?
Fuel tanks aren’t perfectly clean environments, says Muñoz, and driving after the gas light comes on can move the debris through your engine. Why is this a problem? It can clog up your vehicle’s components, damage your air filter and harm your fuel pump. Additionally, he says, when your engine isn’t provided the fuel it needs to run properly, “you can expect it to start misfiring when the tank is really low. A bad misfire can damage your engine or even cause an accident while you’re driving.”
What should you do if the gas light comes on?
When that light comes on, don’t panic—but also, don’t ignore it. Here’s what you should do.
- Get gas — the sooner you can fill up, the better.
- If you’re critically low as you drive around looking for a gas station, turn off the air conditioning and any unnecessary electronics in your car, including the radio and heated or cooled seats. These kinds of electronics don’t use gas, but they can put a strain on your vehicle’s battery, which will shorten the amount of time you have before the engine dies.
- If you know you won’t make it to the gas station in time (e.g., you’re driving in a remote area), Milchtein says it’s worth pulling over and calling for a tow before you run out of fuel, both to protect the fuel pump and ensure you’re not stuck in a car that can’t turn on on the side of the road.
Of course, it’s best to just avoid this situation altogether. “Fill up your tank when you’re at a quarter of a tank instead of waiting for the fuel light to come on,” Milchtein emphasizes.
Does driving with the gas light on save money?
If fuel prices are dropping, Garnand says you may save a few cents, but eventually, it is likely to cost you dollars in terms of damage. If money is tight, he says you are better off filling to ½ tank when you hit a ¼, than pushing your car to empty.
How to calculate remaining miles when the fuel light is on
While it’s hard to nail down exactly how many miles after empty you have left, Garnand suggests the following:
- Fill the tank and note “milage 1.”
- Drive until light comes on.
- Immediately refill and note “milage 2” and how many gallons to full.
- Determine your tank size (using VIN Decode or NARPRO can help)
- Calculate: Milage 2 – Milage 1 = Miles Driven
- Miles Driven / Gallons to Full = Miles per Gallon (MPG)
- Tank Size – Gallons to Full = Gas in Tank
- Gas in Tank X MPG = Maximum distance before you’re stuck.
If that’s too intense, the technology in newer cars may provide an answer: If your car tells you how many miles you can drive on the gas you currently have, it will typically calculate how many miles you can drive when your fuel light goes on as well.
FAQs
Can you drive 10 miles on empty?
Yes, typically you can drive 25 to 50 miles when the gas light comes on says Garnand. “Knowledge is power, but this should be categorized as good to know,” he says. “It is best to refuel at around ÂĽ tank and when you see the light, refuel ASAP.”
What does it mean to dive on fumes?
The term “running on fumes” shouldn’t be taken literally. “You aren’t actually driving on fumes, but rather the last little bit of gas left in the fuel tank,” says Miltchtein. Think of it as a metaphor, not a reality.
How long can you drive on a low battery in an electric vehicle?
Electric vehicles (EV) are a different beast, and the “fuel” system doesn’t work the same way it does on fuel-injected cars for obvious reasons, explains Milchtein. For optimal long-term battery performance in even the most eco-friendly cars, a general rule is to prevent the battery from dipping below 20%.
However, when your EV reads 0% charge, it doesn’t necessarily mean that your car is going to shut down immediately. “There is some reserve power left, but how much depends a lot on the car, type of driving, weather and so on,” she continues, explaining that when the reserve is depleted, an electric vehicle will typically go into “Turtle” mode. “This mode allows you to get to the side of the road or down the block safely, but it will limit your speed, among other things.” If you don’t pull over at that point and your electric vehicle does run completely out of charge, it will slowly roll to a stop (and most will also shift the car to park to prevent it from rolling unintentionally).
Additional reporting by Jeff Bogle
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Sources:
- Chaya Milchtein, automotive educator and author of Mechanic Shop Femme’s Guide to Car Ownership
- Robert Muñoz, automotive electrician and road safety expert at SensibleMotive
- Jim Garnand, ASE Certified Master technician, owner of Hi-Tech Car Care, and president of Neighborhood Automotive Repair Professionals NAPRO)
