
Do you really need premium gas? Photo: Terri Marshall
Don’t over pay if you don’t have to.
Premium is a powerful word. It suggests you don’t settle for second-best.
Some drivers buy premium gas, because they care about their investment. They want their car to have the absolute best fuel available. Does that sound like you? If so, I’ve got some bad news. Unless your owner’s manual says otherwise, buying premium gas is a waste of money.
AAA tested the impact of premium gas on performance, emissions, and fuel economy. It didn’t provide any benefit. 16.5 million Americans bought premium gas in the last year, even though their vehicle didn’t need it. Result: They wasted $2.1 billion dollars in the process, which adds up to an average of $127 per driver. How many yoga classes could you attend with that money?

Luxury rides like the 2016 Jaguar XF need premium. Photo: LeAura Luciano
Some cars–especially luxury and high-performance vehicles–do need premium gas
Car engines are made specifically for the type of fuel they require. Premium octane burns at a higher temperature than regular gas, because it takes more heat (energy/power) to achieve peak performance. Luxury brands like Porsche, Jaguar and Mercedes usually require premium. Here’s a list of every 2016 and 2017 model that requires premium gas.
It’s risky to put regular fuel into a car that requires premium. Fuel will not burn efficiently, which can result in a sticky carbon residue. The carbon is like plaque on your teeth. If you don’t brush for a day, nothing bad will happen. Slack off for a few months and you’ll get stuck with a root canal. Likewise, poorly burned fuel can lead to premature and more costly repairs.

We all want to save gas and money, can your car run on regular?
‘Recommended’ and ‘required’ are not the same thing
Often, it’s ‘recommend’ that a car use premium fuel, but not required. Think of how some food marketers capitalize on the word “natural” leading consumers to assume natural equals healthy, which of course is not necessarily true. You can’t really determine how healthy a food is until you read the label.
The same thing happens at gas stations. Premium gas is presented as a cleanse, detox, or tonic for your hard-working engine. Some marketing suggests premium gas is cheaper in the long-term, because it improves your engine performance and fuel economy. Unfortunately, these claims are exaggerated.
Is premium necessary for your car? Conduct an experiment to find out
Even though premium may be recommend for your car, you might be able to use regular gas. Here’s a simple test (and a little math) to find out.
Before you begin your fuel economy experiment, write down the number of miles on your odometer. This is your starting point. To keep it simple, I recommend fueling up on the same day every week. Subtract the previous week’s mileage from current mileage to calculate how many miles you traveled. Divide that total by how many gallons it took to replenish your tank. This number is your MPG.
Follow these steps for at least a month with both regular and premium gas to confirm your findings. For one month, fuel up with regular gas. Record your mileage at each pit-stop. Save receipts in an envelope so you can easily keep up with the costs. The following month, fuel up with premium gas and repeat the same process. Then, compare the cost and MPG of running on regular fuel versus premium to see if buying premium provided more miles on a tank of gas.
The bottom line may be performance, not cost
Even if you’re not getting a bump in MPG using premium, the cost difference should not be your only consideration. Listen to your engine. If you hear a knocking sound or acceleration feels sluggish when there’s regular fuel in the tank, that means it isn’t compatible with your engine. Switch to premium, even if it’s more expensive.
Still have questions? If so, drop them in the comments. Share this post with your friends so they can save money on gas, too.
Sorry Audra. I have to strongly disagree with this position.
It USED to be that premium was needed for higher compression engines to limit pre-ignition or “spark knock”, but virtually any vehicle will run on “regular” gasoline because of pizo-electric knock sensors.
When a higher grade of quality fuel is used, the control module can use more spark advance which allows for the optimum spark timing, and with the capability of fuel injector control, also the ECM can make best use of not only injector pulse width (amount of fuel) but also injector timing.
When injector timing and spark timing can be implemented at the optimum time, the ability of todays engines (most of which use variable valve timing as well) the amount of fuel used can be greatly lessened and also with a cleaner burn things like spark plugs, oxygen sensors, and catalytic converters stay cleaner longer.
An added benefit with a cleaner, more complete burn is less internal soot left on cylinder walls, which then doesn’t get scraped down the cylinder walls into the engine oil with each piston stroke. Cleaner oil means less wear and tear on engine internal lubricated systems.
With the variable valve timing (VVT) and the electrically controlled solenoids using the engine oil (Pascals Law) to operate the airflow via cam timing, today there are more incidents of failed camshaft sensors and actuators. Root cause-?? Dirty or over extended oil.
The volumetric efficiency of getting the air mass into the cylinders is critical both for emissions and fuel economy. To gain the best from volumetric efficiency, the injector timing and spark timing need to be able to match.
That does not mean all “premium” fuels are the same. Some are just bilge wash, whether regular or premium. There is also more to fuels than just “Top Tier” as well, but that’s a good place to start. Top Tier deals primarily with fuels that keep injectors atomising the fuel properly.
Because the engineers have done a good job developing vehicles, people get away with stuffing “soft coal” through the injectors for years until finally, many things have deteriorated to the point that injectors need to be cleaned/replace, catalytic converters become contaminated, oxygen sensors fail, spark plugs fail and when this is all combined, ultimately there is more electrical stress put on ignition systems and ignition coils as well.
I’ve been monitoring fuels used by real world customers (not pristine lab reports) since the 1980’s and believe me, fuel selection can make a huge difference.
My personal ride is now 15 years old and even when the temperature is below -20-C (around -20-F or close enough to know that it’s REAL COLD-!!) the computer controlled starter solenoid is only energized for LESS THAN ONE SECOND and BAM, the engine is running. Cleaner, quicker, easier starts (which also uses less fuel to get things going) are just one indicator of how much difference a GOOD QUALITY premium fuel can make.
There are more detail, but I’m not writing a book.
A good quality, top tier, premium fuel, ultimately SAVES money, contrary to the short sighted purchase price at the pumps.