Welcome to the Corolla Forum!  :thumbsup::clap:

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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".