2004 Audi A6 problems & reliability
35 owner complaints filed with NHTSA for the 2004 Audi A6, alongside 4 safety recall campaigns. Last verified Aug 7, 2026. Complaints are unverified reports submitted by owners to the federal Office of Defects Investigation.
Each complaint is counted once (by NHTSA case number), even when it names several vehicles.
1 complaint report injuries (1 injured).
Federal crash records (FARS 2020–2023): 2004 Audi A6 vehicles were involved in 3 fatal crashes with 2 occupant deaths. Involvement counts are not adjusted for how many are on the road and do not imply fault or a vehicle defect.
Most reported problems
| Component | Complaints | Share |
|---|---|---|
| Fuel System, Gasoline | 5 | 14% |
| Air Bags | 3 | 9% |
| Electrical System | 3 | 9% |
| Engine and Engine Cooling | 3 | 9% |
| Fuel/propulsion System | 3 | 9% |
| Seats | 3 | 9% |
| Tires | 3 | 9% |
| Wheels | 3 | 9% |
| Electronic Stability Control (esc) | 2 | 6% |
| Exterior Lighting | 2 | 6% |
Component groups as classified by NHTSA. A complaint can name more than one component, so shares may sum to more than 100%.
Mileage when problems occurred
Half of the failures with a reported odometer reading occurred by 73,000 miles (middle 50% between 42,603 and 94,574 miles), based on 27 complaints that included mileage.
Complaints by incident year
What owners report
“- ABS Module has intermittent failures, available for inspection - Anti-lock brakes will not work - Yes, the problem reoccurs and the module loses power and then errors out - Others - VCDS - ABS lights come on and BRAKE light stays illuminated”
Service Brakes · filed Dec 12, 2023
“Re: safety recall 20l8/jy; 08v157000: fuel tank rollover valve modification; vin: (xx); 2004 audi a6 3.0l quattro at5 attached docs: 1. 20l8/jy recall notice. 2. 7.14.2008 & 11.18.18 audi n. Scottsdale, az dealer invoices 3. Audi a6 gas tank diagram. Audi corp email response: "at this time we have identified that the…”
Fuel/propulsion System · filed Dec 9, 2018
“Aftermarket radio: pioneer electronics avh-4100 nex backup camera fails and distracts driver significantly. I have attached a scan of the complaint to pioneer electronics. The radio likely has software defect that causes very distracting failures when operating the back-up camera. Pioneer advertises that this backup…”
Electrical System · filed Jul 25, 2017
Verbatim excerpts from complaints filed with NHTSA. Reports are not independently verified.
Federal defect investigations
- FUEL TANK LEAK
Preliminary Evaluation PE08008 · opened Jan 31, 2008 · closed May 30, 2008 · led to recall 08V157000
Technical service bulletins
151 manufacturer communications (TSBs, service campaigns, warranty extensions) are on file with NHTSA for the 2004 Audi A6. The 10 most recent:
This bulletin provides information on the additional reporting requirements for safety related inquiries.
A0023742052680_4 · Service Bulletin/Repair Instructions · issued Oct 4, 2023
This special notice is to inform dealers to return the parts listed if it meets the criteria provided.
SM 48-2022 · Service Bulletin/Repair Instructions · issued Jun 15, 2022
This informational bulletin explains how to order replacement VIN plates, Safety Certification Labels, etc.
A0021482021205_6 · Service Bulletin/Repair Instructions · issued Jun 25, 2021
This bulletin contains instructions for determining if bushings need to be replaced.
A4021242016453_4 · Service Bulletin/Repair Instructions · issued Apr 21, 2021
This information bulletin contains instructions for technicans on how to ensure their TAC call goes smoothly.
A0020362002047_1 · Service Bulletin/Repair Instructions · issued Apr 16, 2020
Exterior lights, moisture accumulation 2013-2021 A3 Cabriolet, 2016-2018 Sportback, 2004-2005 A4 Cabriolet, 2004-2008 S4 Cabriolet, 2008 RS4 Cabriolet, 2010-2021 A4 allroad, 2018-2021 A5 Sportback, 2010-2012, 2018-2021…
A9419182012749_1 · Service Bulletin/Repair Instructions · issued Dec 6, 2019
New document 2004-2020 A4 allroad, A6 allroad, A8L, R8 Spyder
20AUTIRECHAINS · Service Bulletin/Repair Instructions · issued Dec 4, 2019
Parts are currently blocked from sale at this time.
SM 80-2019 · Service Bulletin/Repair Instructions · issued Oct 1, 2019
This bulletin contains instructions for additional reporting requirements for safety related inquiries (airbag/seatbelts, accidents, fire and overheat damage.
A0019262052680_2 · Service Bulletin/Repair Instructions · issued Sep 30, 2019
00 Software Version Management (SVM), operating instructions
A0019252011732_1 · Service Bulletin/Repair Instructions · issued Sep 17, 2019
TSBs are repair guidance manufacturers send to dealers — they are not recalls and repairs are not automatically free. Full documents are available on NHTSA’s site.
Safety recalls
The 2004 Audi A6 has 4 NHTSA recall campaigns — recall repairs are free at franchised dealers regardless of the vehicle’s age.
Check whether your specific vehicle is affected
Recall campaigns often cover only certain VIN ranges. Enter your VIN on the official NHTSA site to confirm whether your vehicle is included and whether the repair is still open.
Check VIN on NHTSA →Buying a used 2004 Audi A6?
- · Decode the seller’s VIN with our free VIN decoder to confirm the exact year, engine and trim.
- · Check for unrepaired recalls by VIN on NHTSA’s official lookup — recall repairs are free.
- · Owners most often reported problems around 73,000 miles — budget accordingly if the car is approaching that mileage.