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SALT LAKE CITY — Tricia Jenkins knows a thing or two about why she needs to keep her new minivan filled with enough gas.
“I usually go at about a half-a-tank,” she said. “Sometimes, I get down to a quarter-a-tank, but I don’t like to go much lower than that.”
For Tricia, it's a matter of safety. Like many of us, she can't predict when she'll get stuck in traffic.
“There have been many times out here on I-15 that I have been stuck for a long period of time,” she recounted.
It's one reason why experts warn drivers to not let the gas drop below the quarter-tank mark. But, Jeremy Smith of Steve's Automotive Specialists has another. He said the gas in the tank helps keep the fuel pump cool. Keep the tank empty and you can burn out the pump.
“It’s an electric motor, if they’re exposed to air and if there’s not much fuel for that coolant effect,” Smith explained, “they can get hot and they’ll overheat.”
Smith says some carmakers have recently improved fuel pumps to where they can better withstand empty tanks, but there are more issues to consider.
“You get more condensation inside the gas tank if you’re always leaving more air in there,” Smith explained. “And you never know when you’re stuck in a traffic jam, your commute might take 45 minutes longer than you were planning on. Don’t get stuck on the freeway without enough gas to get off. Just fill it up all the way and you’ll be good to go.”
You could be burning money if you’re not buying the right gas for your car. A recent AAA study found Americans waste $2.1 billion annually buying higher octane premium gas their car doesn’t need.
“AAA ran a test,” explained AAA spokeswoman Rolayne Fairclough. “They put cars up on a treadmill and tested for emissions, fuel efficiency, horsepower – all those things. And it found higher octane fuel in a car that only called for regular gasoline had no benefit at all. So, what you’re doing is just wasting money.”
“I’m sure there are people convinced they get better mileage or more power when they do buy premium,” said John Kelly, professor of Automotive Technology at Weber State University.
Conversely, pumping regular gas into a car that needs premium fuel for a high-performance engine can cause problems.
“If you put too low of an octane in an engine, the fuel could ignite before the spark plug ignites it, and you get this detonation or pinging sound that can be pretty harmful,” Kelly said.
If you’re not sure if should gas up with regular, mid-grade or premium – Tricia has an easy solution.
“I just look it up in my owner’s manual, and that’s what I use,” she said.
Where you buy gas also matters.
“I think a lot of people think all gas is the same, the only thing different is the price,” said Kelly. “That’s simply not the case. Where you buy your fuel can make a difference.”
Jeremy Smith says it’s best to look for major brand names because their gas will additives and detergents that are typically better for your car’s engine.
“Different brands of fuel will have different additive packs added to the fuel, which can help reduce carbon in the engine, clean the engine out and make it perform better,” said Smith.
“If you buy gasoline from a major brand gas station, chances of you having a fuel-related problem are pretty slim,” said Kelly. “Automobile manufacturers use Top Tier gasoline when they have to have the Environmental Protection Agency pass their certification tests. If you want a vehicle to operate and run like it was designed to, that’s really the fuel that needs to be in the tank.”
You may have seen fuel additives in auto parts stores boasting increased mileage if you pour it in your tank. Kelly says don’t buy them.
“Those additives are not approved by the vehicle manufacturer,” explained Kelly. “Depending on what additive it is, it could actually cause problems with your vehicle. Just leave it alone, unless it’s sold by the car manufacturer at their parts counter as an official factory additive, which is pretty rare. There’s no tune-up in a can.”
For drivers who just can’t bear to leave the pump a few cents short of an even dollar, you may want to reconsider topping off. That extra fuel can build up enough pressure in the tack to push gasoline into a car’s vapor collection system meant only for vapor.
“If there’s liquid in there, it’s not going to like that. It can cause the emission control system that controls the vapor canister to detect a malfunction,” said Kelly. “You’ll get a check engine light, you’ll have to take it to the shop, see what’s going on and that could cost a lot more money. Just learn to let the pump click off and let it be.”
And have you ever gone to get gas, only to realize you're not quite sure what side that fuel door is on? Well, here's an easy fix. Take a close look at the fuel gauge. You’ll see an arrow next to the gas pump icon. It actually points to the side where you'll find the fill door.
