One problem related to manifold/header/muffler/tail pipe 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.
After driving 800 highway miles from florida, with 400 miles left to go we stopped for the night. The next morning the car was bucking and refused to run. We added a fuel additive and manual shift in order to keep the car running and get it home. On Aug. 27th we changed the fuel filter and took the car for a test drive. The car stalled when going up a hill aprrox. 500 ft from house. It would not restart. The car was towed to the dealer on Aug. 28th and is still there on sept. 20th. So far they have replaced the fuel in the tank and the fuel filter, and the egr valve was replaced. The car is still running sluggish and bucking. They can't find out what is wrong with it. Next they want to take apart the intake manifold even though they are not sure that is the problem. The car is a 2005 and half Jetta diesel with 63,000 miles on it. The car is unsafe to drive and is the car I depend on to take my children back & forth to school (a 20 mile trip one way).