Enterprise Rent-A-Car saved millions of dollars by deleting a standard safety feature from thousands of Chevrolet Impala fleet vehicles, according to the Kansas City Star.

Enterprise purchased about 66,000 2006-08 model-year Impalas without side-curtain airbags, saving the company roughly $175 per vehicle, or about $11.5 million.

After the cars left rental fleets, Enterprise and countless dealers nationwide offered those vehicles for sale on the open market. However, the newspaper reported that Enterprise's Web site advertised the vehicles as having the safety feature.

Enterprise officials defended their decision to delete the side air bags, saying they did not violate any federal mandate. But the St. Louis-based company admitted making a mistake in its online advertising. Enterprise vice president for corporate communications Christy Conrad acknowledged a "glitch" in the system that resulted in 745 Impalas sold from Enterprise's used-car lots to be marked incorrectly, only online, as having side air bags.

Enterprise will send letters to all 745 buyers notifying them of the problem. The company also will offer to buy back the cars, regardless of condition, at $750 above Kelley Blue Book value.

The roughly 3,000 Impalas sold to consumers on Enterprise-owned lots, both properly and improperly advertised, represent just a fraction of the Impalas that the rental company placed on the used-car market by way of auctions and sales to outside dealers.

GM says it has discontinued the fleet-buyers' option of deleting side air bags in the 2009 model Impalas.