5 Ways to Conserve Petrol When You’re Running on Empty

Considering everything that can go wrong with your car, running out of gas is among the most frustrating, because it’s also one of the most preventable. But when you’re out driving and notice your low-fuel light is illuminated, what can you do to make sure the gas you have will get you to the next gas station?

I talked to a few mechanics to find out the best ways to conserve fuel when you’re running on empty and to gauge how far you can expect your remaining gas to take you. “We’ve all made mistakes and let the tank get too low,” says Robert Walden, a longtime mechanic and founder of Vehicle Freak, but your mistake doesn’t necessarily need to result in a walk to the nearest gas station.

How far can you drive on empty?

The good news is that unless you’re driving a fairly old car with an analog fuel gauge, “once the low-fuel light comes on, you will probably see a distance to empty mileage that is usually fairly accurate,” says Andy Saari, an A.S.E. certified master technician and founder of Nexedge Technician. But fairly might not be good enough if you aren’t sure how far you are from a gas station—and while your electronic gauge will give you a better idea of how far you can get on your remaining fuel, Saari says this number can fluctuate depending on the driving conditions.

It’s hard to determine precisely how many miles a car can drive on “empty” or with the low-fuel light on, but generally speaking, you’ll typically make it another 30 to 50 miles before your vehicle stops, says John Lin, owner and head mechanic at JB Motor Works. though once again, this can vary with the car’s model, fuel efficiency, and other factors.

“Idling is the least fuel-efficient method since you’re burning gas and not going anywhere,” Saari explains. “This is why many of today’s vehicles have an auto start-stop feature, which under certain conditions, will shut the engine off at stop signs or when idling.”

How to conserve fuel when you’re almost out of gas

In the event that you’re running low on gas while driving in an isolated area, or stuck in traffic with no fuel station accessible, here are a few strategies for making the fuel you have last as long as possible, courtesy of the mechanics I interviewed:

Turn off the air conditioning

When every ounce of fuel matters, switching off the air conditioning may help reduce engine load, says Saari. However, he says that another common suggestion—turning off your car’s stereo—won’t make any difference in your fuel usage. “The energy usage will be insignificant,” he notes.

Avoid rapid acceleration

If you notice that you’re running low on gas, you may be tempted to increase your speed to get to a gas station faster, but Walden warns against that. “Take it easy on the gas pedal, and avoid speeding up too fast, which wastes gas,” he explains. “I know being late can make you hit the gas, but going slow saves fuel when the tank is low.”

Keep your speed down

While we’re on the subject of acceleration, Lin recommends avoiding driving at high speeds, noting, “Your vehicle’s fuel efficiency decreases rapidly at speeds above 50 miles per hour.”

Avoid hard braking

Along with rapid acceleration, slamming on the brakes can also burn more fuel than necessary, Lin says.

Avoid unnecessary stopping and starting

Smooth, steady driving without frequent stops and starts helps to conserve fuel, says Michael Dominguez, a certified master mechanic and the founder of Car Fixer Guide. “Adjusting your route to minimize stop-and-go traffic is also beneficial,” he adds.

Ultimately, it’s best not to make driving with your low-fuel light on a habit. “[Doing so] frequently can potentially harm the fuel system, as debris or sediments which normally settle at the base of the tank may get sucked into the fuel pump and damage it,” Lin says.