One problem related to power train has been reported for the 2004 Volkswagen Jetta. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2004 Volkswagen Jetta based on all problems reported for the 2004 Jetta.
Vehicle experiences somewhat frequent rough or hard shifts between gears, and reverse gear has suddenly stopped working most of the time - will not engage reverse, but instead acts as if car is in neutral (makes a slight electronic sound when shifted). Renders car highly unsafe to drive without the ability to drive in reverse. Car has only 83,000 miles, and this is considered a "sealed" transmission by Volkswagen; only maintenance required to this point is checking for leaks (per multiple dealers and owner's manual). Very similar to problems experienced in many other automatics w/ the tiptronic feature in Volkswagen (see new beetles of similar model years, where vw issued an extended warranty for the valve body). Have been told by numerous vw-competent techs that the most likely culprit is the transmission valve body, and that vw automatics are widely known for having these problems.