Why do I get better mileage with premium gas?
Premium gives better gas mileage
Because premium gas has a higher octane rating than midgrade or regular gas, it produces a little more power when burnt. Designed for performance cars with large, powerful engines, premium also helps minimize the risk of preignition inside highly-stressed, hot engine cylinders.
“If you mistakenly fill up with regular fuel, your car's ECU will adjust engine timing and performance to work with the lower-octane fuel,” The Drive said. “In most cases, this is OK for the times when there are no premium pumps around, but it's not ideal to run the cheapest fuel possible for extended periods of time.”
“Use premium unleaded gasoline with a posted octane rating of 91 or higher. If the octane rating is less than 91, you could damage the engine and may void your vehicle warranty. If heavy knocking is heard when using gasoline rated at 91 octane or higher, the engine needs service.”
Premium gas is a higher octane gasoline that's typically used in high performance engines. A higher-octane rating means the fuel is better balanced and stabilized against spontaneous combustion, which can cause engine knocking and damage to your vehicle.
Sadly, there's nothing in premium gasoline that would make it last longer than other fuels from the pump. Since the distinguishing feature is the higher-octane levels, the only real benefit you gain is lowering the chance of engine knocking, which isn't much of a threat on most modern fuel systems.
No matter what you've heard, premium-grade gasoline won't do more to clean deposits from your fuel injectors or other parts of the fuel system because today's regular gas contains the same detergent additives. The main difference with premium is its octane rating — 91 or higher compared with 87 for regular octane.
- Buick Envision (with 2.0L turbo)
- Buick Regal (all models)
- Buick Regal TourX (all models)
- Chevrolet Equinox (with 2.0-L turbo)
- Chevrolet Malibu (with 2.0-L turbo)
- Fiat 500L (all models)
- GMC Terrain (with 2.0-L turbo)
- Honda Civic (with 1.5-L turbo)
Luxury cars may require premium gas if they have a high performance or turbocharged engine. Even if you're not buying a luxury car, more luxurious trim levels for a car may offer engine options that require premium gas.
Chevron. Of America's largest nationwide chains, Chevron scores the highest points in overall customer satisfaction. Its reach spans over 7,800 stores, and while some gas stations offer convenient food marts, one location in North Hollywood goes above and beyond gasoline.
“If the octane is less than 91, the engine could be damaged and the repairs would not be covered by the vehicle warranty. If heavy knocking is heard when using gasoline rated at 93 octane, the engine needs service," the owners manual reads.
Do all luxury cars take premium gas?
The answer is, it depends on the make and model of his car. While it is true that some luxury car makers require higher octane fuel – BMW X7 and Lexus LS are two examples – there are plenty of luxury cars that don't need premium gas; the auto maker, however, may recommend it.
In most cases, the vehicle will run fine, but you may experience less power and a decrease in gas mileage. In more serious cases, you may hear engine knocking or valve chatter because the fuel isn't burning right. These things could damage your engine and you should take it to your mechanic.
With a newer vehicle, putting premium gasoline into one that's rated for 87-octane usually does little more than put a hole in your wallet. However, in a classic car, you may want to stop at the pricier pump, no matter what your engine was originally rated to take. Octane isn't an additive.
Can I use regular gas if my car requires premium? Experts advised against switching to regular gas if a vehicle requires premium. If a vehicle requires high-octane gas but is filled with lower-octane gas, drivers risk damaging the powertrain, which includes the engine, transmission and other components, MacDonald said.
Which fuels have the longest shelf life? Propane, alcohol, wood, and charcoal are examples of good emergency storage fuels that can be stored indefinitely and still remain viable.
No, premium gas does not last longer than regular gasoline in a fuel tank. A car owner might only consider the longevity of a car's gas if the vehicle has been sitting unused for an extended period.
There is a common misconception that when you drive a luxury vehicle, you must fill the tank with only premium gas. Due to this misconception, many luxury vehicle owners will buy premium gas, whether or not the vehicle requires it. The truth is that there are many, if not most luxury cars that use regular gas.
Smarter engines protect themselves
First of all, premium gas has a higher octane rating, an important factor in helping prevent engine knock or "pinging." Depending on where you live, this premium-grade fuel could be 90 octane, 91 octane or even 94 octane. That's one reason premium costs more.
Regular gas has the lowest octane rating, Premium has a higher octane and Super (or Supreme or Premium Plus) has the highest octane. Octane is the measure of the fuel's ability to resist “knock”. Knocking or pinging are the loud noises that occur when the air/fuel mixture is incorrect.
Thanks to advances in engine technology, today's cars utilize onboard computers that adjust for variations in fuel so occasionally using cheap gas won't damage your engine. The difference between off-brand and Top Tier gas comes down to the degree of additives that afford more protection for your engine.
Is cheaper gas worse for your car?
SACRAMENTO, Calif — Lower quality, off-brand gas can be bad for your engine, reports the American Automobile Association (AAA), with the potential to increase emissions from your vehicle that can impact its performance.
Costco's gas may often be the cheapest in town, but it's still high-quality. Kirkland Signature fuel meets Top Tier standards, which means it has deposit control additives to clean your engine and help it run more efficiently.
Pumping fuel.
The reason is simple: Directing gas into a fuel tank while a car is running is harmless, provided that there isn't a spark nearby. Indeed, watch a NASCAR or Formula 1 race, and that is exactly how pit crews refuel — with the race car running.
Regular Gas: Mercedes-Benz Vehicles. Your Mercedes-Benz is a quality-engineered, precision machine, and as such, it's tuned to run only on premium gasoline. Remember, the difference between premium and regular gas is octane.
We recommend always using the minimum octane rating or higher when refueling your vehicle. Choosing an octane rating lower than what is listed for your model year vehicle could lead to engine knocking, which can result in permeant damage to your engine in the long run.
The fuel designed specifically for use in BMW's high-compression engines is 91+ octane fuel. This means that you get more miles to the gallon, because it optimizes engine function, meaning that little fuel is wasted, allowing you to go further on a single tank of gas.
No matter your model, BMW recommends using only premium-unleaded fuel. That's not to say your BMW won't run on lower-grade fuel, but premium-unleaded fuel will maintain its quality in the long run, letting you drive at peak performance consistently.
When switching from a 91 octane tune to a 93 octane tune you can expect to see an increase of 5 to 6 more horsepower on top of the gains you are already getting from an 87 octane Bama tune.
Shell Gasoline is also certified TOP TIER™, a higher standard for engine cleanliness and performance set by auto manufacturers.
If it says to use fuel with an octane rating of 87, filling your tank with a higher-octane fuel doesn't provide any extra benefits to your engine. If your vehicle manual says to use fuel with an octane rating of 89, going below that grade can affect your engine's performance and fuel efficiency.
Does higher octane gas increase mpg?
Related Stories. Raising the octane rating (also known as the anti-knock index) doesn't change the energy content of a gallon of gasoline.
For the majority of vehicles, using higher octane fuel may improve performance and mileage and even reduce CO2 emissions when the vehicle is working hard, such as when towing a trailer or carrying heavier than normal cargo, especially in hotter weather.
Chevron. Of America's largest nationwide chains, Chevron scores the highest points in overall customer satisfaction. Its reach spans over 7,800 stores, and while some gas stations offer convenient food marts, one location in North Hollywood goes above and beyond gasoline.
Regardless of whether your car calls for regular or premium, the best choice for ongoing performance and economy is a TOP TIER gasoline. Recent AAA testing found TOP TIER gasolines keep internal engine components up to 19 times cleaner than gasolines that only meet minimum EPA standards.
Luxury cars may require premium gas if they have a high performance or turbocharged engine. Even if you're not buying a luxury car, more luxurious trim levels for a car may offer engine options that require premium gas.
No. If anything you'll get worse gas mileage with a full tank because you're carrying a heavier load (more fuel = more weight).
However, when you mix two different octane levels, you get their average. So, if you have exactly half a tank of 87-octane gas and half a tank of 93-octane gas, then you've just got a full tank of 90-octane gas. Adding higher octane gas to an engine designed to use lower octane gas will never be a problem.
Mixing regular or mid-grade gasoline (87 – 89 octane) with premium gasoline (91 – 93 octane) won't be harmful to cars designed to run on regular gasoline. However, mixing these gasoline types in cars designed for premium gasoline may result in engine knocking and damage to the fuel system depending on the car.