Gasoline Detergents Standard Improves Mileage

Your local gas station probably offers you 3 levels of gasoline. These typically have different levels of octane in them and you will generally get a little better mileage for the more expensive type.

There are many different additives that can be in a companies brand of gasoline. This differentiation can have a big impact on your vehicle.

One type of additive is a detergent which cleans your engine. Without some level of detergents engine deposits form and this causes reduced engine performance.

In 1994 four auto manufacturers (BMW, General Motors, Honda, and Toyota) recognized the gasoline marketers were not putting enough detergents in their gasoline and the U.S. EPA was not mandating a high enough minimum standard. In fact, after the EPA set a minimum standard gasoline producers reduced the amount of detergents in their gas because the standard was so low.

Vehicle owners were left suffering with reduced engine power, reduced fuel efficiency, increased driving upsets (rough idle, stalling and surge), decreased acceleration and increased emissions.

These four automakers decided to do something about the lack of detergents and poor running vehicles created their own class of gasoline called 'Top Tier Detergent Gasoline'. To meet this qualification gasolines require a higher level of detergents.

In 1994 a few gasoline distributors adopted this new industry standard and since then it has expanded to many retailers like: QuikTrip, Chevron, Conoco, Phillips, 76, Shell, Entec Stations, MFA Oil Company, Kwik Trip/Kwik Star, The Somerset Refinery, Chevron-Canada, Aloha Petroleum, Tri-Par Oil Company, Shell-Canada, Texaco, Petro-Canada and Sunoco-Canada.

I discovered this gas by trying the 'silver' gas out at Shell. I thought it would increase performance for only one tank of gas due to the higher octane. Surprisingly, later fillups with the cheaper bronze gasoline still saw a 5% increase in mileage, not bad for an aging 5 year old car.

By P. Fezziwig, contributor to Green Cars Now , a website devoted to promoting fuel efficient vehicles and Car Repair Ratings, a consumer ratings site on mechanics.