Car care · Elgin Auto Sales & Service Center · Elgin, IL
How to Get Better Gas Mileage
How you drive and how you look after your car both affect your gas mileage. These tips follow fueleconomy.gov, the U.S. Department of Energy and EPA fuel economy site, with the size of each effect as the site reports it.
10% to 40%mileage lost to aggressive driving
Above 50 mphwhere mileage usually drops fast
About 1%per extra 100 lbs. of weight
Up to 3%from correct tire pressure
The short answer
Drive smoothly, keep to the speed limit, and avoid long idling. Fueleconomy.gov says aggressive driving can lower gas mileage by roughly 15% to 30% at highway speeds and 10% to 40% in stop-and-go traffic, and mileage usually drops quickly above 50 mph. Remove roof cargo boxes and extra weight when you do not need them, keep your tires at the recommended pressure, use the recommended grade of motor oil, and have a lit check engine light looked at promptly.
Driving habits that save gas
Fueleconomy.gov estimates the following effects on fuel economy:
| Habit | What fueleconomy.gov says |
|---|---|
| Drive sensibly | Speeding, rapid acceleration and braking can lower gas mileage by roughly 15% to 30% at highway speeds and 10% to 40% in stop-and-go traffic. |
| Observe the speed limit | Gas mileage usually decreases rapidly above 50 mph. Slowing down 5 to 10 mph is estimated to improve fuel economy 7% to 14%. |
| Use cruise control | On the highway, cruise control helps you hold a constant speed and in most cases saves gas. |
| Avoid excessive idling | Idling can use a quarter to a half gallon of fuel per hour, depending on engine size and air conditioner use. Restarting takes only about 10 seconds worth of fuel. |
| Skip the roof box | A large roof-top cargo box can reduce fuel economy by around 2% to 8% in city driving, 6% to 17% on the highway and 10% to 25% at 65 to 75 mph. Rear-mount boxes or trays cost much less. |
| Remove excess weight | An extra 100 pounds can reduce mileage by about 1%, and the effect is larger on smaller vehicles. |
From Driving More Efficiently (fueleconomy.gov), read November 9, 2026. Fueleconomy.gov also notes that driver feedback devices helped the average driver improve fuel economy by about 3% in one study.
Keep your car in shape
Maintenance matters too. Fueleconomy.gov lists these:
- Fix engine problems promptly. A lit check engine light could be as minor as a loose gas cap or a more serious issue that reduces fuel economy, so have the vehicle inspected.
- Keep tires properly inflated. Correct pressure improves gas mileage by 0.6% on average and up to 3% in some cases; under-inflated tires lower mileage about 0.2% for every 1 psi drop in the average pressure of all tires. Use the pressure on the driver's door jamb sticker, glove box or owner's manual, not the maximum printed on the tire sidewall.
- Use the recommended grade of motor oil. That can improve gas mileage by 1% to 2%; for example, using 10W-30 in an engine designed for 5W-30 can lower mileage by 1% to 2%. Look for "Energy Conserving" on the API performance symbol.
- Know what an air filter does. On modern fuel-injected, computer-controlled gasoline engines, replacing a clogged air filter does not improve fuel economy, but it can improve acceleration.
From Keeping Your Vehicle in Shape (fueleconomy.gov), read November 9, 2026.
Why gas mileage drops in winter
Fueleconomy.gov says a conventional gasoline car's city gas mileage is roughly 15% lower at 20 degrees F than at 77 degrees F, and can drop as much as 24% on short trips of 3 to 4 miles. Hybrids are typically affected more. Causes include cold engine oil and other fluids, a longer warm-up, heaters and defrosters, denser air and lower tire pressure. To help:
- Park in a warmer place, such as a garage.
- Combine trips so you drive less often with a cold engine.
- Minimize idling to warm up; most manufacturers recommend driving off gently after about 30 seconds.
- Do not use seat warmers or defrosters more than necessary.
- Check your tire pressure regularly.
- Use the type of oil your manufacturer recommends for cold weather driving.
- Remove roof racks and other accessories that add wind resistance when not in use.
From Fuel Economy in Cold Weather (fueleconomy.gov), read November 9, 2026.
Service at Elgin Auto Sales & Service Center
Check engine light on, or due for an oil change or a tire check? Schedule service or see our service specials.
Our service department at 1200 E. Chicago St. in Elgin is open Monday to Friday 8 a.m. to 5 p.m. and Saturday 8 a.m. to 4 p.m., and is closed Sunday. Get directions.
Better gas mileage FAQ
What wastes the most gas?
Fueleconomy.gov says aggressive driving (speeding, rapid acceleration and braking) can lower gas mileage by roughly 15% to 30% at highway speeds and 10% to 40% in stop-and-go traffic.
What speed gets the best gas mileage?
Each vehicle is different, but fueleconomy.gov says gas mileage usually decreases rapidly at speeds above 50 mph.
Does idling waste gas?
Yes. Idling can use a quarter to a half gallon of fuel per hour, and restarting takes only about 10 seconds worth of fuel, so turn the engine off when parked.
Does tire pressure affect gas mileage?
Yes. Under-inflated tires lower gas mileage by about 0.2% for every 1 psi drop in the average pressure of all tires, and correct pressure improves mileage 0.6% on average.
Will a new air filter improve my gas mileage?
Not on modern fuel-injected, computer-controlled engines, according to fueleconomy.gov. It can improve acceleration. On older carbureted engines it can improve both by a few percent.
Why is my gas mileage worse in winter?
Cold oil and fluids, a longer warm-up, heater and defroster use, denser air and lower tire pressure all reduce mileage. City mileage can be roughly 15% lower at 20 degrees F than at 77 degrees F.
What are your service hours?
Monday to Friday 8 a.m. to 5 p.m. and Saturday 8 a.m. to 4 p.m. We are closed Sunday.
Keep your car running efficiently
Visit us at 1200 E. Chicago St. in Elgin.
Sources
Driving, maintenance and cold-weather fuel economy figures are from fueleconomy.gov, the official U.S. government fuel economy site run by the Department of Energy and the EPA, read November 9, 2026. This is general information; your owner's manual is the authority for your vehicle. Our address and service hours are from our own website, checked the same day. Photo is of our dealership.
- Driving More Efficiently (fueleconomy.gov), U.S. Department of Energy and U.S. EPA, read November 9, 2026
- Keeping Your Vehicle in Shape (fueleconomy.gov), U.S. Department of Energy and U.S. EPA, read November 9, 2026
- Fuel Economy in Cold Weather (fueleconomy.gov), U.S. Department of Energy and U.S. EPA, read November 9, 2026
- Home page: address, Elgin Auto Sales & Service Center, read November 9, 2026
- Service page: service hours, Elgin Auto Sales & Service Center, read November 9, 2026