At a minimum, gasoline should meet ASTM specification D 4814 in the United States or CAN/CGSB-3.5 or 3.511 in Canada. Some gasolines contain an octane-enhancing additive called methylcyclopentadienyl manganese tricarbonyl (MMT).
We recommend against the use of gasolines containing MMT. See Additives for additional information.
Gasoline Octane
California FuelChevrolet Cobalt Service & Repair Manual. Engine Leak Inspection
A visual inspection must always
be performed to confirm the presence of aftermarket components, potential
collision damage, or areas of concern.
Before moving the vehicle inspect
underneath for signs of oil on the ground to aid in identifying the leaks
location.
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