I’m a Mechanic: These Common Misconceptions About Fuel Efficiency Are Costing You Money

Getting the most miles per gallon is a bit of a game when you own a vehicle. If you have a larger SUV, you might be driving a gas guzzler around town. On the other hand, if you have an electric hybrid vehicle, you might be saving money by not going to the pump all the time. However, that’s not always the case, with fuel efficiency not necessarily having a clear, cut and dry distinction when it comes to cars .

See Also: I Have Driven Over 250 Car Models: These Are the 3 Best and Worst for Your Money

Learn More: How To Get $340 Per Year in Cash Back on Gas and Other Things You Already Buy

“I think many people assume that any car that boasts fuel efficiency and a lower upfront cost will end up having a shorter lifespan,” explained Ben Michael, the director of auto at Michael & Associates . “While this may have once been the case, I don’t think that’s a proper assumption anymore.”

Michael went on to describe how fuel efficiency has become a top priority for lots of manufacturers and car models, and general technologies “…have improved which allow newer cars to last longer. So, fuel-efficient cars today can last just as long.”

GOBankingRates was able to get some mechanic and car experts points of view on what misconceptions about fuel efficiency are costing you money.

Sponsored: Owe the IRS $10K or more? Schedule a FREE consultation to see if you qualify for tax relief.

The “Squeaky Wheel”

Misconception: One has to be a ”squeaky wheel” to get good mileage for a small car.

James White, an auto repair expert with Amazing Moves , highlighted the fact that “…the latest data available for the ten most efficient cars on the market, for the 2023 model year, many of which are midsize or large.”

Discover More: 6 Car Brands With Reliable Used Cars

According to White, technologies fuel efficiency has been improved in the area of high technology diesel engines, blended vehicles, rechargeable electric vehicles, plug-in hybrid electric vehicles, direct fuel injection, turbocharging, efficient transmissions, and low rolling resistance tires.

Plus, White added that “…aerodynamic developments make standard vehicles travel with high fuel efficiency.”

Manual vs. Automatic Transmissions

Misconception: Automated manual transmissions are rated to give better fuel economy than conventional automatic ones.

There have been strides in the automotive industry to improve automatic transmission, which has only enhanced the fuel efficiency and performance across the board.

“In most cases, they have observed that the automatic equipped car tends to be more fuel-efficient than its manual transmission counterpart,” White said.

Start Up vs. Idle Engine

Misconception: It’s worse to start up a car due to higher fuel requirements than idling the engine.

“Startup loss is low in contemporary engines when employing fuel injection,” explained White “it is even more efficient when the engine warms up.”

White went on to say that starting up your car “[drains fuel (from a quarter to half a gallon per hour) and therefore runs from 1 to 2 cents per minute.”

“Idling for more than 10 seconds consumes more fuel than restarting the engine,” Joyce Gutierrez, an automotive expert for 4WheelOnline added. “Modern vehicles are designed to restart efficiently, making it more fuel-efficient to turn off the engine when stopped for longer periods.”

“Switch off the engine if you don’t intend to travel for more than 10 seconds,” White recommended. “Do not leave your engine running while waiting at traffic lights or where frequent stood-idle-stared cycles are required.”

Warm-Up Time

Misconception: Engines in most vehicles require a bit of warm-up time before they are capable of running at optimal capacity.

In White’s experience, most of the cars on the road today are in good shape, and can be driven within a few seconds of putting the key into the ignition.

“Consequently, do not apply very high or low loads before the engine gets to its normal working temperature,” White said. “While there are ways of doing a winterization on a car, the fastest way to warm up an engine is by driving it.”

Premium Gas Is Better

Misconception: Premium gasoline improves fuel economy.

“One of the most persistent myths surrounding gasoline is that using premium, high-octane fuel will improve a vehicle’s fuel efficiency,” Gutierrez explained. “However, this belief is unfounded and contradicts how gasoline octane ratings work.”

Gutierrez continued by describing how “[t]he octane rating of gasoline measures its resistance to premature ignition or ‘knocking’ during combustion. Higher octane fuels are designed to withstand higher compression ratios and cylinder pressures before igniting, which benefits high-performance engines or those with high compression ratios.”

Eliot Vancil, CEO of Fuel Logic LLC said that “…most automobiles are built to operate efficiently on regular gasoline. Using premium fuel in an engine that does not require it will not appreciably improve performance or mileage, resulting in wasted money. According to the Federal Trade Commission, you don’t profit from the higher price unless your car especially requires premium gasoline.

However, Gutierrez added that “…premium fuel provides no tangible benefits in fuel economy for most modern vehicles that run on regular unleaded gasoline .”

Fuel Efficiency vs. Car Costs

Misconceptions: Fuel efficiency declines as the car ages, but the price of the vehicle rises.

Cars and other vehicles are the most effective when used for several years, provided they are well-maintained, in White’s professional opinion.

“For fuel economy, more studies from EPA demonstrate that the efficiency keeps rising during the break-in phase,” described White. “Only if the vehicles are not well maintained do they see a relative drop in fuel economy in vehicles which could be as old as 10 to 15 years.”

Here’s a bit of advice: Regularly replace the air filter. It’s a cost-effective solution and ensures great fuel efficiency.

To perform this task, White instructs car owners to “first unpack the air filter from its container, then take off the old filter from your vehicle, [and finally] throw the old filter away or dispose [of] it properly.”

“It is not directly related to a car’s fuel economy, but reinstalling a fresh air filter may help address existing issues with the engine,” White noted. “While fuel-injected engines’ strategies control the [fuel-to-air] mixture’s ratio depending on the engine speed automatically, it is advisable to use a clean filter to reach the peak.”

To increase fuel efficiency and save money, Vancil offered the following suggestions:

• “ Maintain your vehicle regularly. Regular oil changes, air filter replacements, and engine tune-ups can increase mileage by up to 4%.”
• “Drive sensibly. Aggressive driving, such as fast acceleration and braking, can reduce your gas mileage by 15-30% on highways and 10-40% in city driving.”
• “Lose extra weight. An additional 100 pounds in your vehicle can reduce your MPG by around 1%.”
• “Use the brakes on the freeway. Maintaining a consistent speed can help you save fuel.”

This article originally appeared on GOBankingRates.com : I’m a Mechanic: These Common Misconceptions About Fuel Efficiency Are Costing You Money