fuel additives VOLKSWAGEN JETTA GLI 2014 1B / 6.G Owners Manual

If unleaded Premium grade gasoline is specified for your vehicle, then Volkswagen recommends using TOP TIER Detergent Gasoline with a minimum octane rating of 91 AKI (95 RON). For more information on TOP TIER Detergent Gasoline, please go to the official Web site, http://www.toptiergas.com.
The gasoline grades most commonly sold in the United States and Canada have the following octane ratings, which can usually be found on the filler pump:
x Premium grade: 91 to 96 AKI
x Regular grade: 87 to 90 AKI
Unleaded gasoline
Unleaded gasoline is available throughout the USA and Canada. Volkswagen recommends that you do not take your vehicle to places where unleaded gasoline may not be available.
Gasoline containing alcohol or MTBE
You may use unleaded gasoline blended with alcohol or MTBE (methyl tertiary butyl ether), commonly referred to as oxygenated fuels, if the blended mixture meets the following criteria:
Blends of gasoline and methanol (wood alcohol or methyl alcohol):
x Anti-Knock Index (AKI) must be 87 or higher.
x Blend must contain no more than 3% methanol.
x Blend must contain more than 2% co-solvents.
Blends of gasoline and ethanol (grain alcohol or ethyl alcohol):
x Anti-Knock Index (AKI) must be 87 or higher.
x Blend must contain no more than 10% ethanol.
Blends of gasoline and MTBE:
x Anti-Knock Index (AKI) must be 87 or higher.
x Blend must contain no more than 15% MTBE.
Seasonally adjusted gasoline
Many fuels are blended especially for winter or summer conditions. When seasons change, Volkswagen suggests that you buy fuel at busy stations where the seasonal adjustment is more likely to be made earlier.
WARNING
Starting fluids can explode and cause a run-away vehicle condition.
x Never use starting assist fluids.
NOTICE
x Never use fuel with an octane rating lower than 87 AKI/91 RON. Using lower octane fuel may cause expensive engine damage.
x Never use leaded gasoline! Leaded gasoline will severely damage your vehicle's catalytic converter.
x Methanol-blended fuels that do not meet the criteria listed above may cause corrosion and may damage plastic and rubber parts in the fuel system.
x Never use fuels that contain lead or other metals (check listing on the fuel pump). Even lead replacement gasoline (LRP fuels) contain metallic additives in high concentrations. They can damage the engine.

x Do not use fuels that fail to meet the criteria above, or with contents that cannot be identified.
x If you cannot tell whether a particular fuel blend meets the criteria above, ask your service station or its fuel supplier. If you notice a loss of fuel economy or drivability and performance problems using one of these fuel blends, we recommend that you switch to unblended fuel.
x Using fuels that are different from those specified above can damage your vehicle's engine and fuel system and cause performance problems.
x Damage to the engine and fuel system and performance problems caused by using fuels that are different from those specified above or by using “starting assist fluids” are not the responsibility of Volkswagen and are not covered under the Emission warranties or any other Volkswagen Limited Warranty.
Even a single tank full of leaded fuel can do major damage to the catalytic converter and degrade its effectiveness in reducing polluting emissions.
If you notice a loss of fuel economy or drivability and performance problems using one of these fuel blends, we recommend that you switch to unblended fuel. Never use fuel line antifreeze offered for gasoline engines.
Gasoline additives

x Do not use fuel that is labeled at the pump as containing metal. Lead replacement fuel contains high concentrations of metallic additives. Engine damage could result.
x Fueling your vehicle just one time with leaded fuel or fuel that contains other metallic additives can affect the performance of the catalytic converter and cause extensive damage to it.