It has been reported that the demand for the diesel versions of Volkswagen Jetta, Golf, Passat, Beetle and Audi A3 has been on an increase. In case of only Jetta Sport Wagon around 90 percent of the sales was recorded to be of the TDI models.
However, only a few of the TDIs sold were reported to have faced fuel pump failing. Feb 2011 survey performed by NHTSA revealed that there were 160 incidents of stalling in 2009-2010 Golf and Jetta TDIs. In the same report it was declared that “fuel system damage incurred by use of fuel not complying to ASTM-D-975 Grade 2 S15 (B5 or less biodiesel content) standards will not be covered under warranty.”
In addition, Volkswagen highlighted that the company had 121 reports of customers admitting mis-fueling their cars. This meant that those people used regular unleaded fuel instead of diesel.
Several Passat TDI owners also reported stalling issues but the NHTSA hasn’t done any investigation yet. It may be that the issue arose because of the incapacity of the fuel tank of dealing with the diesel that is contaminated by gasoline.