The National Highway Traffic Safety Administration (NHTSA) is opening an investigating into 2009 Volkswagen Jetta TDI cars after receiving seven complaints that the engine stalled while driving. It is estimated that about 38,000 diesel Jetta TDI and Jetta SportWagon TDI models could be affected. The NHTSA thinks the problem may be related to potential fuel system contamination issues.

VW spokesman Kerry Christopher said that Volkswagen takes safety issues very seriously and will fully cooperate with the NHTSA’s investigation.