China’s quality inspector has started an investigation into potential defects on a locally produced Volkswagen sedan after a growing number of complaints from owners.

The General Administration of Quality Supervision, Inspection and Quarantine has contacted VW about complaints of broken rear shafts affecting its Sagitar sedan and asked the automaker to remedy the problem, the regulator said in a statement on its Web site.

The agency has also requested that affected car owners provide feedback to assist in the investigation. Volkswagen recalled 384,181 vehicles in China last year to replace defective transmissions after state broadcaster China Central Television featured owners’ complaints about cars equipped with the company’s proprietary DSG gearbox technology.

Sagitar owners made 216 complaints about problems with the model’s rear axle on the national Defect Information Collection System between July 30 and Aug. 12 — about half the total 435 complaints posted during the period.

FAW-Volkswagen, the Chinese joint venture company that produces the vehicle, issued a statement on July 22 saying expert analysis showed that the problems with the Sagitar were isolated and not a design and manufacturing issue.

The company also said it reserved the right to take legal action against those spreading “untrue” information.