See also:

OnStar®
If equipped, this vehicle has a comprehensive, in-vehicle system that can connect to a live Advisor for Emergency, Security, Navigation, Connection, and Diagnostic Services. See OnStar Overview. ...

If No Steam Is Coming from the Engine Compartment
If an engine overheat warning is displayed but no steam can be seen or heard, the problem may not be too serious. Sometimes the engine can get a little too hot when the vehicle: - Climbs a long h ...

Gasoline Specifications (U.S. and Canada Only)
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 methylcyclopentadieny ...