General Motors Co.'s short-lived effort to sell cars online through eBay Inc. (EBAY) will end this week, the auto maker said Tuesday.

The program, launched Aug. 11 as a pilot program in California, had not driven major sales for the auto maker, which is under pressure to stem a decades' long slide in U.S. market share.

The eBay venture was one of GM's first moves after emerging from bankruptcy protection in July. At the time, GM CEO Fritz Henderson said the project was part of an effort to make car shopping more convenient.

"We decided right now this was not the best use of our marketing dollars," GM spokesman John McDonald said. "We're trying new things and we're experimenting and taking risks. We were stepping into uncharted waters with this."

Rob Chesney, vice president of eBay Motors, said the program generated 1.5 million visits to its GM page, resulting in about 15,000 qualified leads, or roughly 70 leads for each of the 227 California car dealers participating in the program.

GM and eBay declined to say how many cars were sold through the program, though GM's McDonald said the number of direct sales was small. More valuable, McDonald said, is the interest generated by having vehicles listed on the popular site.

The auto maker, struggling to get new consumers to even consider buying a new GM vehicles, has gone to great lengths to woo buyers. The latest effort is a 60-day, money-back guarantee launched earlier this month. GM determined it didn't make sense to have the eBay program running alongside the money-back promotion and a separate "May the Best Car Win" ad campaign, McDonald said.

The eBay deal was initially set to end Sept. 8 but was extended through the end of the month.

Under the program, shoppers using special eBay sites can purchase GM cars and trucks at a "buy it now" price, or bargain online with a dealer.

But several dealers complained that too many people submitted ridiculously low bids, forcing staff to sift through offers that were highly unlikely to result in sales.

One suggested that eBay's reputation as a destination for bargain hunters was inconsistent with GM's need to play up the quality of its cars.

"We don't need to have fire sales. We need to promote the quality of the product," said Richard Slade, general manager at FH Dailey Chevrolet in San Leandro, Calif.

McDonald said better education among dealers and customers may have helped head off some of the troubles, and would be a focus should GM attempt a similar program in the future. EBay's car-shopping site operates differently than the traditional bidding platform consumers are accustomed to, leading to some confusion, he said.

"Anytime you have something new like this there's always going to be someone whose expectation wasn't met," he said.

EBay's Chesney said the eBay leads had a higher conversion rate than what GM typically sees through other sales channels nationwide. He also suggested that eBay would evaluate the discontinued program in hopes it might be able to develop another effort to sell new cars. He declined to elaborate.

Separately, GM on Thursday will announce that it has completed a deal to sell its Saturn division to Penske Automotive Group Inc. (PAG). GM has been working since June to finalize a sale of the brand to auto magnate Roger Penske. Under the deal, Penske, the second largest U.S. auto retailer by revenue after AutoNation Inc. (AN), will buy Saturn's brands, service and parts and distribution operations, but not its manufacturing operations.

The Penske deal was first reported by the Detroit Free Press.

-By Sharon Terlep and Scott Morrison, Dow Jones Newswires; 248-204-5532; sharon.terlep@dowjones.com