There is a direct relationship between current gas prices and the fuel economy of cars being sold – when fuel is expensive, car shoppers look for fuel efficient options. Despite a general shift toward more fuel-efficient vehicles, drivers put less emphasis on this concern when gas prices drop. According to a recent report by TrueCar.com, the average fuel economy of new cars sold in July 2012 was 23.1 miles per gallon (MPG). This is higher than the average fuel economy during the same period last year (21.6 MPG) and just higher than the average in May of this year (23.0 MPG).

"There is a very strong correlation, nearly 71 percent, between TrueMPG and average gas prices since January of 2010, indicating that prices at the pump influence consumer preferences," said Jesse Toprak, vice president of market intelligence at TrueCar.com. "Manufacturers have been responding by offering a larger mix of smaller vehicles and improving efficiencies on their existing larger vehicles, as evidenced by the significant improvement in TrueMPG in the recent years."

The cost of fuel spiked in early summer and then began to fall slightly month-over-month, which could explain why fuel economy became less of a concern for some drivers. This average will likely fall in coming years, despite consumer behavior, as manufacturers work to meet federally issued fuel economy guidelines. By 2025, all car companies must have a fleetwide fuel economy average of 54.5 MPG. Until then, drivers don't have to buy new cars to take advantage of vehicles with good fuel economy. NJ Auto Auction carries a variety of makes and models, from subcompact cars to hybrid options. Plus, every car on the lot is CARFAX certified, so buyers know they'll be getting behind the wheel of a reliable ride.