The manufacturer of air bags linked to four deaths made another 30,687 inflators with an incorrect part that can lead to similarly damaging ruptures in newer vehicles, U.S. regulators said, adding to questions about the scope of the defects in Takata Corp. products.

Takata will recall the SDI-X inflators manufactured from June 16, 2008, to June 20, 2014, the National Highway Traffic Safety Administration said in a statement on its website. An incorrect outer baffle could cause the unit to rupture, the agency said. Owners will be notified by vehicle manufacturers.

The defective inflators were in General Motors Co. and Nissan Motor Co. models the automakers decided to recall in June and October, respectively, according to documents on the NHTSA website and an email from Alby Berman, a Takata spokeswoman. GM recalled 29,019 Chevrolet Cruze small cars from model years 2013 and 2014.

The new recalls pertain to vehicles newer than those covered by the broader Takata actions, which involve products from the 2000 through 2008 model years.

The regulator Thursday said Nissan’s Infiniti unit would recall 1,848 SUVs that could propel metal fragments out of its air bags toward occupants. That was an expansion of the previous recalls, Berman said.

The part at fault is different from the one that led to 7.8 million U.S. vehicles being called in for repairs, an effort that was stepped up in recent weeks by federal regulators because of the severity of the defect. That recall includes vehicles from 10 automakers, including Nissan, Honda Motor Co. and Toyota Motor Corp., and is linked to four fatalities.

U.S. regulators have questioned whether Takata is moving quickly enough to produce replacement parts to repair previously recalled cars. (Bloomberg)