A6 Quattro Wagon V6-3.2L (BKH) (2006)
Filtration element was too fine in the original in-line filter (part number 4F0 201 801 A) for the leak detection pump. In some cases, the filter
becomes obstructed by particulate build-up that impedes tank pressure normalization. This condition leads to nonlinear corrections in tank
pressure, thus causing a thumping noise.
Production Solution
Vehicles produced after the specified VIN break are equipped with an improved filter (part number 4F0 201 801 B).
Service