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. Fuel Pump, Replace
Removal
1.
Relieve fuel system pressure as outlined
under "Precautions."
2.
Drain fuel tank.
3.
Raise and support vehicle.
4.
Disconnect connector and remove fuel
...