5 simple ways to save on gas

This post comes from Jeanine Skowronski at partner site MainStreet.

Gas prices continue to rise to atmospheric levels, leaving many Americans to wonder how they can save on fuel during the forthcoming summer months.

Fortunately, while little can be done to stop escalating costs, there are a few steps motorists can take to minimize the toll it takes on their pocketbooks.

"The biggest way to save on gas is to lower the amount of fuel you use," Jen Funkhouser, the co-founder and CEO of CarCheckup, tells MainStreet. The most obvious way to do this, of course, is to simply drive less, but for those who prefer to stay on the road, there are some small changes to your driving habits you can make.

• What are you doing to save on gas?

Turn off your car. "Minimize the time you spend in idle," Funkhouser says, explaining that any time you find yourself stopping for more than 30 seconds or more -- minus time spent in traffic -- you should turn off your car.

Drive defensively. You should also cut back on driving fast, unnecessarily changing lanes, breaking hard and, conversely, slamming down on the accelerator since, according to experts (and the U.S. Department of Energy), aggressive driving eats up more fuel than defensive driving does. In fact, according to recent government estimates, gas mileage usually decreases rapidly at speeds above 60 mph and drivers should assume that each 5 mph over that limit costs an additional 24 cents per gallon for gas.

Perform necessary repairs. The Energy Department estimates that fixing a serious maintenance problem can improve your gas mileage by as much as 40%. If you don't have enough money to pay for a major repair, the DOE suggests some smaller adjustments, like keeping your tires properly inflated (improving gas mileage by 3.3%) and getting a tune-up, which improves gas mileage by an average of 4%. You could also just get rid of that junk in your trunk, since extra weight will also reduce your car's fuel efficiency.

Use your smartphone. According to Andrea Woroch, a consumer savings expert for The Frugals, a network of money-saving websites that includes CouponSherpa.com, drivers looking to save on fuel should take advantage of all the help their smartphone has to offer.

"There are apps for just about everything these days and indeed, there is an app that will help you save at the pump," she says. Woroch's digital suggestions include using GasBuddy, a free GPS app for iPhones, Android and Windows phones that locates gas stations in your area and lists the current price per gallon.

• MSN Autos: Find the cheapest gas near you

She also recommends the free CheapGas app for the iPhone, which will navigate you to the least expensive gas station on your route.

Get a credit card with gas rewards. Those who are truly looking to save and also happen to be in the market for a new credit line should consider getting a card that earns points on gas purchases.

• Find a better credit card

"Credit cards that offer gas reward programs are very popular because you can build points or receive cash back for purchases made at the pump with the card," Woroch explains.

While these cards can offer anywhere from 1% to 5% back in rewards on purchases, consumers should just make sure to read the fine print carefully before settling on one, since some rewards programs come with restrictions.

"Some cards offer a high reward percentage as an introductory offer but it may drop significantly after the initial period," Woroch explains. "Many cards are only valid for use with one gas station company."

If you fear the credit commitment, you can also sign up for a specific gas station or chain's loyalty program. Various programs are offered through BP, Chevron/Texaco and ExxonMobil.

More on MainStreet and MSN Money:

• The 9 biggest driving distractions
• Cheap ways to soup up your car
• Gas prices aren't stopping luxury SUV buyers
• 9 everyday items that cost more than gasoline
• Why you should love $5 gas
• Drivers saying no to high gas prices?