Does it really matter what brand of gas I use?
It does matter because certain brands have more detergent additives that can help prevent carbon deposits from building up inside your engine.
These brands are known as Top Tier and use more detergents and/or other additives than the EPA requires. Many vehicle manufacturers recommend Top Tier gasoline to ensure that owners don't complain about poor engine performance, fuel economy, or any other problems.
Major oil companies, such as Shell, ExxonMobil, and Chevron have adopted the voluntary Top Tier Standards for detergent additives.
Vehicle manufacturers claim that other gas brands can lead to carbon deposits in combustion chambers. This can cause engine knock (or pinging) and can also affect intake valves.
However, this does not mean that you should use Top Tier gasoline.
Practically speaking, smaller independent gasoline stations and brands are usually cheaper than major brands. This is a good thing for those on a tight budget. Some motorists may not be able to get gas at the Top Tier stations regularly due to distances. If you are driving on interstate highways and your tank is almost empty, you will need to get as much gasoline as you can.
Hyundai and Kia suggest that owners who don’t use Top Tier gasoline should add a fuel system cleaner to their tanks periodically to remove any gunk or deposits. To find out what your manufacturer has to say about Top Tier gasoline, gasoline, and fuel additives, you should consult your owner's manual.
If you frequently use other brands of gasoline, it is a good idea to stick with top-tier companies like Shell or Chevron.
For more details, check at Courtesy Automotive Service Center.