General Motors Co. has told Chevrolet dealers to stop selling 2013-14 Chevy Cruze sedans because of an air bag problem.

Some vehicles have a driver’s air bag inflator that was assembled with an incorrect part, GM spokesman James Cain said.

GM expects to resume sales by the end of this week; it’s not yet clear how many vehicles are affected. GM also expects to recall vehicles already sold.

The automaker sold 119,330 Cruzes in the United States in the first five months of this year, making the sedan its bestselling passenger car. In all of 2013, it sold 238,192 of the vehicles.

“We are in the process of figuring out how many bad parts were shipped by the supplier and how many vehicles are impacted,” Cain said.

The inflator was made by Takata Corp.

Separately this week, automakers started to recall millions of vehicles to replace defective explosive charges, also made by Takata, in air bags that can send metal shrapnel flying at occupants during a crash.

Car companies have called back at least 31.4 million vehicles in the United States this year, breaking the industry’s record of 30.8 million, set in 2004.

The new Chevy Cruze air bag issue is not related to that issue, which was caused by the chemistry of the propellant in the inflator. GM described the latest problem as a mechanical issue.

GM has issued 44 recalls covering 17.8 million cars in the United States this year.