The Volkswagen Passat B6 (type 3C) marked a major technical turning point for the model. Abandoning the B5's longitudinal platform (shared with Audi) for the transverse PQ46 platform (derived from the Golf V), it gained in interior space and introduced a multitude of new technologies (electric parking brake, directional headlights, dual-clutch DSG gearbox). While its road qualities, comfort, and finish are undeniable, the B6 is sadly famous for the catastrophic reliability of its first years of production, particularly concerning the 2.0 TDI Pumpe-Düse (PD) diesel engines and its onboard electronics. The switch to Common Rail (CR) technology in late 2008 saved the model's reputation at the end of its career.
The Volkswagen Passat B6 is a car with two faces. Models produced between 2005 and mid-2008, equipped with the 2.0 TDI Pumpe-Düse engine, are true trouble spots (injectors, oil pump, cylinder head, electronics) and should be AVOIDED unless you have a clear service history proving that all chronic defects have been corrected. In contrast, technically revised models from late 2008 onwards, equipped with Common Rail (CR) diesel engines and more reliable electronics, are excellent, robust, and economical long-distance cars. If you're looking for a diesel, imperatively aim for a 2009 or 2010 model. For petrol, prefer the placid 1.6 MPI for peace of mind, or budget for timing chain work on the TSIs.