Gasoline Specifications; California Fuel; Additives- Page 254

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Gasoline Specifications

It is recommended that gasoline meet specifications
which were developed by the American Automobile
Manufacturers Association and endorsed by the
Canadian Vehicle Manufacturers’ Association for better
vehicle performance and engine protection. Gasolines
meeting these specifications could provide improved
driveability and emission control system performance
compared to other gasolines.

In Canada, look for 
the “Auto Makers
Choice” label on 
the pump.

Canada Only

California Fuel

If your vehicle is certified to meet California Emission
Standards (see the underhood emission control label), 
it is designed to operate on fuels that meet California
specifications. If this fuel is not available in states adopting
California emissions standards, your vehicle will operate
satisfactorily on fuels meeting federal specifications, but
emission control system performance may be affected. The
malfunction indicator lamp may turn on (see “Malfunction
Indicator Lamp” in the Index) and your vehicle may fail a
smog

-

check test. If this occurs, return to your authorized

GM dealer for diagnosis. If it is determined that the
condition is caused by the type of fuel used, repairs may
not be covered by your warranty.

Additives

Some gasolines that are not reformulated for low
emissions may contain an octane

-

enhancing additive 

called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline whether
the fuel contains MMT. General Motors does not
recommend the use of such gasolines. Fuels containing
MMT can reduce the life of spark plugs and the
performance of the emission control system may be
affected. The malfunction indicator lamp may turn on. 
If this occurs, return to your authorized GM dealer 
for service.