Other than when you pay the bill, you likely don’t give much thought to fuel. But there’s a lot more to automotive gasoline than just “fill ’er up,” and so we’ve assembled some fun facts you might not have known about fuel.
Octane isn’t an additive
It sounds like fuel companies create premium fuel by simply dumping in more octane, but instead, the octane level depends on how the gasoline is refined. It’s a more sophisticated process to make higher-octane gas, which is generally why it’s pricier.
And while it also sounds like quicker-hotter-burn stuff, it’s actually the other way around. In basic terms, higher-octane fuel is more stable and less volatile than lower-octane gas. In the intense heat of a high-compression engine, such as in a sports car, lower-octane fuel can ignite unevenly. Higher-octane gas creates an evenly-moving “flame front” that maximizes power, and protects against potentially-harmful engine knock.
The station only stocks two grades of gas
The pump will offer at least three levels: regular-grade 87 octane, mid-grade 89, and premium 91, and with some stations offering up to 94 octane. But there are only two tanks of gasoline in the ground, of the lowest and highest grades. If you select one in between, the pump simply mixes them to the correct ratio.
The pump knows when you’ve had enough
Fill your tank, and just like magic, the pump knows when to stop. That magic is actually a small hole near the tip of the nozzle, with a tiny pipe attached. As the tank fills with fuel, air comes out and up the pipe. When the fuel level comes up to the hole in the nozzle, it creates a vacuum in the tube. That triggers a switch in the nozzle handle to shut off the flow.
Resist the temptation to top up. The vehicle’s emissions system includes a charcoal canister, which captures stray gas fumes from the fuel tank, and then sends them to the engine for burning. If you overfill, liquid gas can get into the canister and damage it.
Your phone won’t “spark” a conversation
There’s a warning on the pump not to use your cell phone while you’re gassing up your car. The sign warns it’s because the phone could spark, resulting in an earth-shattering kaboom!
Well — not really. It’s because when you’re on your phone, you’re paying attention to the call and not on pouring a highly-flammable liquid into your tank, which is where your focus should be. It’s all about reducing distraction.
Why 9/10 cents? The taxman knows…
That nine-tenths of a cent on the price started in the 1930s in the U.S., and it’s still around today because nobody wants to be the first to take it down. It started when the government increased the fuel tax by a fraction of a cent.
That was a big deal when gas was only around 10 cents a gallon, and it was during the Depression. If retailers advertised gas at 10.9 cents, drivers only saw it as a dime, not eleven cents. There’s no legal requirement to put the .9 at the end of the price, but when all the other stations are advertising $1.199, nobody’s bumping theirs up to $1.20.
‘E’ is for “Ethanol”
Ethanol is a plant-based renewable fuel, and almost all gasoline and diesel sold in Canada contains some of it. It’s named for the renewable percentage: for example, E10 is 10 per cent ethanol and 90 per cent gasoline, while B5 is five per cent biofuel mixed with 95 per cent diesel.
There’s a federal minimum of five per cent renewable in gasoline, and two per cent in diesel. Some provinces then add their own minimums. That’s over each oil company’s entire volume, and how it’s parceled out can differ. Some blend the ethanol fairly evenly over all grades, while others sell ethanol-free premium, and correspondingly increase the amount in lower grades. You may have to research to find out what’s sold where.
‘D’ is for “Diesel,” and also for “Don’t Mix ‘Em”
One nozzle handles all the various gasoline grades, while diesel is always a separate nozzle. The diesel nozzle is also larger, so it’s harder to fit it into a gasoline vehicle. And yet people still occasionally pump the wrong fuel.
Diesel in a gas vehicle clogs the fuel filter and injectors, and the engine won’t run. Gas in a diesel is far more serious. It’s more combustible than diesel and will ignite erratically, and that can cause irreparable engine damage. In either case, if you add the wrong fuel, don’t start the engine, not even to move it away from the pump. Push it out of the way, call a tow truck, and have your vehicle taken to a shop for the fuel system to be drained and cleaned.
