One problem related to diesel engine has been reported for the 2004 Volkswagen Passat. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2004 Volkswagen Passat based on all problems reported for the 2004 Passat.
In the 2004 vw Passat tdi (diesel engine) the balance shaft & oil pump are driven by a chain. The chain failed at 101,000 miles and stopped engine lubrication instantly. Required unsafe maneuver in traffic to get off road to a safe stopping spot.