Buick PARKAVENUE 1994 Manual page 233

But don't worry if you hear a little pinging noise when
you're accelerating or driving up a hill. That's normal
and you don't have to buy a higher octane fuel to get rid
of pinging. It's the heavy, constant knock that means
you have a problem.
What about gasoline with blending materials that
contain oxygen (oxygenates), such as MTBE or alcohol?
MTBE is "methyl tertiary-butyl ether.'' Fuel that is no
more than 15% MTBE is fine for your vehicle.
Ethanol is ethyl or grain alcohol. Properly-blended fuel
that is no more than 10% ethanol is fine for your vehicle.
Methanol is methyl or wood alcohol.
NOTICE:
Fuel that is more than 5% methanol is bad for
your vehicle. Don't use it. It can corrode metal
parts in your fuel system and also damage
plastic and rubber parts. That damage wouldn't
be covered under your warranty. And even at 5%
or less, there must be "cosolvents" and
corrosion preventers in this fuel to help avoid
these problems.
Gasolines for Cleaner Air
Your use of gasoline with deposit control additives will
help prevent deposits from forming in your engine and
fuel system. That helps keep your engine in tune and
your emission control system working properly. It's
good for your vehicle, and you'll be doing your part for
cleaner air.
Many gasolines are now blended with oxygenates.
General Motors recommends that you use gasolines with
these blending materials, such as MTBE and ethanol. By
doing so, you can help clean the air, especially in those
parts of the country that have high carbon monoxide
levels.
In addition, some gasoline suppliers are now producing
reformulated gasolines. These gasolines are specially
designed to reduce vehicle emissions. General Motors
recommends that you use reformulated gasoline. By
doing so, you can help clean the air, especially in those
parts of the country that have high ozone levels.
You should ask your service station operators if their
gasolines contain deposit control additives and
oxygenates, and if they have been reformulated to
reduce vehicle emissions.
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