— TOP TIER gas is advertised as a better way to keep your engine clean for just a few pennies more per gallon.
But talk is cheap, so researchers decided to put the marketing slogans to the test and determine if TOP TIER fuel really can improve engine performance by removing carbon deposits that build up in the engine.
Automakers are always concerned about deposits because of how those deposits cause problems with emissions, performance and fuel economy.
In 1996, the Environmental Protection Agency (EPA) forced all gasoline suppliers to add minimum levels of detergent due to carbon deposits gumming up engines, but some automakers didn't think the EPA minimum was high enough.
TOP TIER gas contains detergent additives that go beyond minimum levels mandated by the EPA to help cars achieve better performance and fuel economy by keeping the engines clean.
But convincing consumers to pay a few cents extra per gallon hasn't always been easy because research shows 73 percent of drivers choose gasoline based on price. Additionally, about 75 percent of drivers choose a gas station based on location and not every station sells TOP TIER fuel.
The study was conducted by a certified engine testing lab hired by the American Automobile Association (AAA) to measure how TOP TIER gas influences intake valve and combustion chamber deposits compared to typical gasoline.
After just 4,000 miles of driving, non-TOP TIER gas caused 19 times more engine deposits than TOP TIER fuel, something that surprised researchers who saw first-hand what extra detergent additives can do to keep an engine clean.
Breaking down the numbers, TOP TIER gas left 34 milligrams of deposits on each intake valve compared to 660 milligrams when using non-TOP TIER fuel. In addition, TOP TIER gas helped to reduce carbon deposits throughout the entire engine.
Researchers also wanted to know if switching to TOP TIER will reverse damage caused by carbon deposits and found that switching gas does help reverse engine deposits. Even if all the deposits aren't erased, running a car a few thousands miles on TOP TIER gas will help with hesitation and idling problems.
As for the cost, owners would pay 3 cents more per gallon on average based on using TOP TIER gas over the course of a year, a small price to pay to maintain an engine.
Consumers also shouldn't confuse "premium" fuel with TOP TIER gas as TOP TIER relates to the amount of detergents, not octane levels. If a station sells TOP TIER, it will be available in all three octane levels: Regular, mid-grade and premium.
So where can you buy TOP TIER gas? To date, these licensed brands offer the fuel at most locations:
- BP/Amoco Ultimate
- BP Regular
- BP Silver
- Break Time
- Costco Gasoline
- Diamond Shamrock
- Kwik Star
- Kwik Trip
- Kwik Trip Express
- Metro Petro
- Ohana Fuels
- Phillips 66
- PUMA Energy Caribe
- Road Ranger
- Sunoco Ultratech
- Tri-Par Qwik Stop