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A fuel additive is used to keep the combustion chambers, valves and fuel injector tips clean and functioning properly. Not many of them on the market are very effective.
There is no need or benefit from using Premium fuel unless the owners manual for the vehicle says it's required. Indeed, lower fuel economy can be expected with Premium fuel.
Using Premium gas in a vehicle that doesn't require it, wont help the engine. Save your money. :thumbsup:
Paying a Premium for High Octane Gasoline?
http://www.consumer.ftc.gov/articles...ctane-gasoline
Unless it’s recommended by your owner’s manual, don’t spend the money on high octane gas. In most cases, there’s no benefit. Higher octane helps only if you have problems with your engine “knocking.”
Read Your Owner’s Manual
"Unless your engine is knocking, buying higher octane gasoline is
a waste of money. Premium gas costs 15 to 20 cents per gallon more than regular. That can add up to $100 or more a year in extra costs. Studies indicate that altogether, drivers may be spending hundreds of millions of dollars each year for higher octane gas than they need.
It may seem like buying higher octane “premium” gas is like giving your car a treat, or boosting its performance. But take note: the recommended gasoline for most cars is regular octane. In fact, in most cases,
using a higher octane gasoline than your owner's manual recommends offers absolutely no benefit. It won't make your car perform better, go faster, get better mileage, or run cleaner. Your best bet: listen to your owner's manual.
The only time you might need to switch to a higher octane level is if your car engine knocks when you use the recommended fuel. This happens to a small percentage of cars".