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

The program, launched Aug. 11 as a pilot program in California, had not driven major sales for the auto maker, according to dealers and early sales figures.

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.

GM, now controlled by the U.S. government, is under intense pressure to stem a decades' long slide in U.S. market share.

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.

The eBay deal was initially set to end on 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.

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; 248-204-5532; sharon.terlep@dowjones.com