I was at the dentists office this morning reading the December 2010 Car and Driver. They had a 4 page advertisement for the Volt and in it, they refer to the gas engine as a generator and also had a reference (I forget the exact wording) to it being purely electric with a backup generator if the battery runs low.

From Chevy's web site 2011 Chevy Volt | Chevrolet

The term generator implies that the gas motor only provides electrical energy to the batteries.

Here is the jalopnik article with all kinds of helpful links to Chevy's deceit.

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