oxygen VOLKSWAGEN EOS 2007 Owners Manual

Octane rating
Octane rating indicates a gasoline's ability to resist engine-damaging “knock” caused by pre-ignition. Using the correct grade of gasoline is very important to help prevent engine damage and loss of engine performance.
The recommended gasoline octane rating for your engine is listed on a label inside of the fuel filler flap. This rating may be specified according to AKI (CLC) or RON (ROZ) standards.
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.