There are 3 owner-reported engine complaints for the 2004 Audi A6in NHTSA's database. These are unverified consumer reports and may not reflect confirmed defects.
TL* THE CONTACT OWNED A 2004 AUDI A6. WHILE DRIVING AT 20 MPH, SMOKE APPEARED FROM THE ENGINE COMPARTMENT AND THE VEHICLE CAUGHT FIRE. A POLICE REPORT WAS FILED AND THERE WERE NO INJURIES REPORTED. THE VEHICLE WAS DESTROYED. THE VEHICLE WAS NOT INCLUDED IN NHTSA CAMPAIGN NUMBER: 06V198000 (ELECTRICAL SYSTEM). THE MANUFACTURER WAS NOT MADE AWARE OF THE FAILURE. THE FAILURE MILEAGE WAS 103,000.
REPLACED CYLINDER BANK 1 RIGHT SIDE! *TR
I AM WRITING ABOUT MY 2004 A6 AVANT, WHICH HAS 78,000 MILES. AT A RECENT OIL SERVICE AT AN INDEPENDENT GARAGE, IT WAS SUGGESTED THAT THERE WAS A PROBLEM WITH THE CATALYTIC CONVERTERS. EXHAUST WAS LEAKING FROM BOTH SIDES, I WAS TOLD. I TOOK THE CAR TO MY AUDI DEALER, WHERE THEY CHECKED THE EXHAUST SYSTEM. THE MECHANIC WHO EXAMINED THE CAR CONCURRED THAT THE CATALYTIC CONVERTERS NEEDED TO BE REPLACED. UNDER A FEDERALLY MANDATED WARRANTY, THE CATALYTIC CONVERTERS ARE COVERED FOR EIGHT YEARS OR 80,000 MILES. YET THE DEALER HAS DECLINED TO COVER REPLACEMENT BECAUSE THE "CHECK ENGINE" LIGHT WAS NOT ON. I WAS GIVEN A REPAIR ESTIMATE OF $2,400. *TR
Complaints are unverified consumer reports submitted to NHTSA. A high complaint count may reflect vehicle popularity, not defect severity. Data sourced from NHTSA public records.
Data synced from NHTSA on Apr 26, 2026