The Cash for Clunkers Program went into effect recently, but so did changes to the official EPA-estimated mpg ratings of several cars. For example, the 1987 Mercury Grand Marquis, according to CNN Money, was rated a combined 18 mpg last week, but as the program began this week, the rating for this year, make and model jumped to 19 mpg on Monday.
While a change of 1 mpg seems relatively insignificant, the Grand Marquis rated at 19 mpg no longer qualifies as a trade-in worth up to $4,500 under the Cash for Clunkers Program. Since the new legislation was made retroactive to July 1, car dealers have been including the rebate in their deal calculations before the rebates were available. Furthermore, dealers offered the anticipated credit as an immediate benefit to the customer with the expectation of being able to file for the credit. But this change by the EPA resulted in some cars no longer qualifying for the credit already given to the customers and as a result, some dealers have been asking customers for the money back or threatening to take back the new car.
According to the EPA, 78 models became ineligible for the credit after the reassessment of mpg calculations while 86 other models have become eligible, so there may be credits available for some who may not be aware. The recalculations occurred for model years 1985-2007 to use the same calculation that began in 2008. This puts all cars released since 1985 on the same scale, and this was a change required by the new legislation.
My 2004 Honda Civic changed from an official EPA combined estimate of 34 mpg in the old calculation method to 30 mpg in the new calculation method. You can see how your car’s estimates changed at the car finder at FuelEconomy.gov.
Updated June 24, 2016 and originally published July 29, 2009.