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 Replacement
1.
Relieve fuel system pressure.
2.
Drain fuel tank.
3.
Raise and support vehicle.
4.
Disconnect fuel pump module fuel feed
and return line quick connect fittings from fuel filter ...