Two problems related to manifold/header/muffler/tail pipe have been reported for the 2008 Volkswagen Jetta. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2008 Volkswagen Jetta based on all problems reported for the 2008 Jetta.
The problem is the intake manifold and the intake valves stuck from excessive carbon buildup. It was replaced in Feb 2011 and now needs replacing again. Problem is, now I'm out of the warranty period and the dealer is saying I would have to pay for this myself. They also added that there was only a 1 year warranty for the first time this was replaced in Feb 2011. There have been many complaints on the intake manifold and no recall from Volkswagen. If the decarbonization had been done when the intake manifold had been replaced the first time, this would have never happened again.
I was told by the vw dealership that there is known defect with the motor that is part of the air intake manifold which causes the valves to stick and not allow the proper mixture of air/gas, causing the engine to misfire. . . . At times, the misfire can be intense and could possibly cause someone to lose control of their vehicle ("bucking sensation"). I found many threads on the internet regarding the vw Jetta (2. 0t engine) and a problem with the air intake manifold, but yet, vw has never issued a recall for the problem.