An Audi commercial that aired in theatres and online in China is drawing ire for comparing women to used cars - another bump in the road for the German automaker, which once enjoyed nearly limitless growth in the country.

The advertisement opens in a pastoral setting, with a bride and a groom about to take their vows. But the mother of the groom frantically interrupts, rushing up the aisle to "inspect" her would-be daughter-in-law.

With a stare, the woman proceeds to pinch the bride's nose, pull back the bride's ear and then examine the inside of the bride's mouth.

"What are you doing?!" the horrified groom asks in Mandarin, as he pulls his mother away.