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.
Chevrolet Cobalt Owners Manual. DIC Warnings and Messages
These messages appear if there is a problem detected
in one of your vehicle's systems.
A message clears when the vehicle's condition is no
longer present. To acknowledge a message and clear it
from the display, press and hold any of the DIC buttons.
If the condition is still present, the warnin ...