With small car sales exploding thanks to record gas prices, GM finds itself unable to build enough Chevy Cobalts to satisfy demand. Now a parts shortage is further complicating the situation. GM had planned to run a double shift this Saturday at the Lordstown, OH plant that assembles the Cobalt and Pontiac G5, but at least one unidentified supplier has apparently been caught flat-footed and unable to meet demand. Cobalt sales have been up about 10% for the year, but fell 27% in August, a decline GM blames on supplier shortages. Presumably G5 production is also affected, but Aveo clone enthusiasts can rest comfortably knowing that plans for the Pontiac G3 remain in full swing. [Marketwatch]