One problem related to tank assembly has been reported for the 2001 Audi A4. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2001 Audi A4 based on all problems reported for the 2001 A4.
Excessive gas fumes from car. Dealer and other service center looked for problem several times. After car was unfit to drive - smelled so bad from gasoline fumes - a service garage removed the fuel tank. The fuel was seeping through molded in plastic connection fittings on top of the tank at their molded interface to the tank - the tank is a poly type tank. The tank was replaced. This is clearly a design defect. Had the fumes been near an ignition source a possible fire or worse could have resulted. It is my opinion that the dissimilar materials used for the tank and fittings lost their seal over time. Audi of America has shown no interest in dealing with this. Since there were 4 fuel tanks available on a Friday and on the following Monday, there were none, so I had to wait up to 2 additional weeks to get a tank - I suspect they are keenly aware of this defect. This car has been garage kept, I am original owner, and it has no accidents. I have the original failed fuel tank at this time. Date of repair 6/29/09 to 7/21/09.