Dave Schembri, president of Smart USA acknowledges premium fuel is recommended however he said “you could use regular gas — there’s no damage to the car.

Something everyone took for granted and very few even gave a second thought, has become a very complicated and highly discussed topic since its prices have gone wild.

That topic is of course gasoline!

Smart dealers recommend using premium (91 octane or better) gas in your new Smart car. But others say it's not mandatory and does not void your warranty.

However, using premium gas is better on your cars motor and in the end more efficient.

Purchasing a premium grade, high octane gas for your Smart car is like exercising, you may not feel the change immediately but you know it's the appropriate thing to do.

When it comes to choosing between gasoline retailers, you may discover that shelling out a little extra at the pump has a significant influence on the performance of your Smart car.

We suggest you use a (TOP TIER Detergent gasoline retailer) premium grade fuel for your first dozen fill ups. This will assist in preventing unwanted wear to the block, pistons rings and spark-plugs and may help avoid any impact on in-use emissions and driver satisfaction.

Using a TOP TIER detergent gasoline retailer may help drivers avoid lower quality gasoline which can leave deposits on critical engine parts, which reduces engine performance, something both the drivers and automakers want to avoid.

In 1995 our EPA mandated using detergent control additives in all gasoline. This was to help prevent the build-up of carbon deposits in engines, which in turn increased tailpipe emissions.

Now many gasoline retailers provide fuels with lower-quality additive packages and it is estimated that 60 percent of gas sold in the USA are near the minimum level of detergency allowed by law.

Some sources say the EPA's minimum level of detergency is not sufficient, to prevent deposit build-up in some cars.

Sulfur in the fuel creates corrosion, and when combusted will form corrosive gases that attack the engine, exhaust and environment.

This can build up deposits on fuel injectors and on intake valves. Others can build up deposits in combustion chambers and may lead to intake valve sticking. This material can cause less efficient mixing of air and fuel and result in an incomplete combustion in some cycles.

These lower levels of additives can have negative impacts on engine performance and vehicle responsiveness.

It is possible deposit build-up in certain vehicles happen in as little as 5,000 miles and some of those vehicles can experience cold start drivability problems as a result.

Types of gasoline additives include metal deactivators, corrosion inhibitors, oxygenates and antioxidants.

Some TOP TIER Detergent retailer's regular and mid-grade gasoline has in excess of twice the quantity of detergents that is compulsory by the EPA.

These levels of protection helps prevent the build-up of carbon deposits on your Smart's intake valves or fuel injectors. However unlikely, if you've used cut rate gasoline, you may already have intake valve or fuel injector deposits, which may need to be cleaned up.

These are some of the retailers known to be on the TOP TIER.

• QuikTrip
• Chevron
• Conoco
• Phillips
• 76
• Shell
• Kwik
• Texaco

TOP TIER Detergent gasoline retailers must meet the high TOP TIER standards with all grades of gasoline to be approved by 6 of the top automakers as providing TOP TIER Detergent Gasoline.

In addition, all gasoline outlets carrying the brand of the approved retailer must meet the TOP TIER standards.

Gas is gas the difference is the additives use in the gas.

"Top tier" gasoline’s has more additives which keeps your engine cleaner and often give better economy.

So, we recommend using retailers like these for the first 3500 miles of your Smart cars life and if you follow just a few of the fuel saving tips you’ll save enough money to afford premium gas for your Smart car every time you go to the pump.

Try these fuel saving guidelines

• Slow down.
• Keep your tires properly inflated.
• Avoid jackrabbit starts.
• Pace you’re driving.
• Use your air conditioner sparingly.
• Avoid lengthy engine idling.

1. Driving at 65 miles per hour rather than 55 miles per hour reduces fuel economy by about 2 miles per gallon.
2. Under-inflated tires can decrease fuel economy by up to 1 mile per gallon.
3. Abrupt starts require about twice as much gasoline as gradual starts.Unnecessary speedups, slowdowns and stops can decrease fuel economy by up to 2 miles per gallon.
4. The use of air conditioning can reduce fuel economy by as much as 2 miles per gallon.