The recall covers certain A6 and A7 cars from the 2012 through 2014 model years.
The Volkswagen luxury brand said in government documents that the fuel lines have a compression point to make them easier to install. But over time, that point can weaken and may leak fuel.
The documents posted Tuesday by the National Highway Traffic Safety Administration say the cars were made between Jan. 25, 2011 and Sept. 13, 2013. Audi says no fires or injuries have been reported.
Owners will be notified starting Feb. 5. Dealers will replace the faulty fuel lines.