 The first pre @-@ production test car based on the final Volt design was built in June 2009 , in Warren , Michigan , and by October 2009 , 80 Volts had been built and were tested under various conditions . On March 31 , 2010 , the first factory @-@ built Volt was produced at the Detroit Hamtramck Assembly Plant in order to test the production line and for quality control purposes , both of the tooling and the pre @-@ production vehicles produced before regular production began . 
