The car has an issue with the fuel tank. The original diesel tank became swollen and would no longer accept fuel from the pump. The fuel tank was replaced by a mechanic, but the same problem reoccurred approximately one week later. The mechanic carried out a leak-off test on the injectors to check for excessive pressure being returned to the fuel system but did not identify any fault. No engine management or warning lights are illuminated, and the cause of the issue remains undiagnosed. The vehicle is therefore being sold as seen, with this fault requiring further investigation and repair by the purchaser. Audi A6 2.0/3.0 TDI (2013) - Runs and drives but has an unresolved fuel tank/filling issue.