There are 8 owner-reported fuel system complaints for the 2004 Audi A6in NHTSA's database. These are unverified consumer reports and may not reflect confirmed defects.
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 20L8 REPAIR WAS SPECIFIC TO THE DRIVER'S SIDE OF THE VEHICLE. THE DEALERSHIP IS INDICATING THIS CURRENT RECOMMENDED REPAIR IS SPECIFIC TO THE PASSENGER SIDE OF THE VEHICLE." "SINCE WE ARE SHOWING THE 20L8 COMPLETED IN JULY OF 2008 AND THE ORIGINAL 20L8 REPAIR IS SPECIFIC TO DRIVER'S SIDE ROLLOVER NIPPLE VALVES, ACCORDING TO THE DEALERSHIP THIS CURRENT REPAIR IS UNRELATED TO THE RECALL." "CURRENTLY PER THE NHTSA WEBSITE, THE 20L8 IS NOT SHOWING AS AN OPEN RECALL, SO I WOULD BE UNABLE TO SPEAK TO HOW THEY WOULD REACT TO INFORMATION REGARDING A CLOSED RECALL." 'WE HAVE NO EVIDENCE SUPPORTING AN INCORRECT REPAIR BEING PERFORMED IN JULY OF 2008, SO AT THIS TIME WE WOULD BE UNABLE TO PROVIDE ASSISTANCE TOWARDS THIS REPAIR." CURRENT EMISSIONS CHECK ENGINE LIGHT (NOV 18, 2018) IS DIAGNOSED BY THE AUDI DEALER AS A GAS TANK LEAK. ALSO, THERE IS A STRONG ODOR COMING FROM GAS TANK. DEALER QUOTED TO REPLACE THE ENTIRE TANK (SEE ATTACHED #2). THERE ARE SEVERAL ROLLOVER VALVES ON EACH SIDE OF THE GAS TANK ON THE TOP SIDE (SEE ATTACHED #3 GAS TANK DIAGRAM). RECALL (SEE ATTACHED #1) DOES NOT ADDRESS "DRIVERS SIDE OR PASSENGER SIDE" OF GAS TANK. DEALER CLAIMED THAT BACK IN 2008 THAT THEY DID NOT EVEN LOWER THE GAS TANK FOR THE REPAIR. IN SUMMARY: MY VEHICLE CURRENTLY HAS A GAS TANK LEAK ON TOP OF THE GAS TANK COMING FROM THE ONE OR MORE ROLLOVER VALVE NIPPLES ON TOP OF THE GAS TANK. THE SAFETY RECALL ADDRESSES REPAIRING AND REINFORCING THESE LEAKING ROLLOVER VALVE NIPPLES SO A REPAIR REQUEST SHOULD BE COVERED BY THE RECALL. PARTS OF THIS DOCUMENT HAVE BEEN REDACTED TO PROTECT PERSONALLY IDENTIFIABLE INFORMATION PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
WHEN ENGINE IS COLD, USUALLY BELOW 0 DEGREES FUEL SPRAYS FROM INJECTORS. THIS COULD IGNITE ON EXHAUST MANIFOLDS CAUSING CAR FIRE.
TL*THE CONTACT OWNS A 2004 AUDI A6. THE CONTACT STATED THAT WHILE STARTING THE VEHICLE, A STRONG ODOR OF GASOLINE EMITTED INSIDE AND AROUND THE VEHICLE. THE CONTACT MENTIONED THAT THE CHECK ENGINE LIGHT ILLUMINATED. THE FAILURE RECURRED SEVERAL TIMES. THE VEHICLE WAS TAKEN TO THE DEALER, WHERE IT WAS DIAGNOSED THAT THE FUEL TANK COLLAPSE AND NEEDED TO BE REPLACED. THE MANUFACTURER WAS MADE AWARE OF THE FAILURE. THE FAILURE MILEAGE WAS 146,569.
SIGNIFICANT GAS LEAK CAUSED BY BROKEN GAS "IN TANK SENDING UNITS" HOUSING AND SEAL. GAS WILL LEAK AND FILL THE INSIDE OF THE CAR WITH FUMS AS WELL AS UNDER THE CAR. REPLACEMENT REQUIRED BUYING A REVISED DESIGN SENDING UNITS THAT INCLUDE ALL THREE SENDING UNITS. THE PRICE IS HIGH ~$500 AND THE CONSEQUENCES VERY DANGEROUS. MY CAR IS: 2004 AUDI A6 [XXX] 2004 A6Q 2.7T INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6). *TR
TL*THE CONTACT OWNS A 2004 AUDI A6. THE CONTACT STATED THAT WHEN REFUELING THE VEHICLE OVER THE THREE QUARTER CAPACITY LEVEL, A SUBSTANTIAL AMOUNT OF FUEL WOULD LEAK UNDERNEATH THE VEHICLE NEAR THE EXHAUST PIPE. THE VEHICLE WAS TAKEN TO AN AUTHORIZED DEALER FOR DIAGNOSTIC TESTING AND STATED THAT THE FUEL TANK ROLLOVER VALVE WAS LEAKING. THE VEHICLE WAS NOT REPAIRED. THE CONTACT EXPRESSED SIGNIFICANT CONCERN OF THE SAFETY RISK INVOLVED. THE FAILURE MILEAGE WAS 90,000. THE VIN WAS UNAVAILABLE.
2004 AUDI A6 SEDAN, 3.0 ENGINE DEVELOPED A SUDDEN LOSS OF POWER JUST BEFORE VEHICLE STALLED WHILE DRIVING ON HIGHWAY AT 65 MPH. VEHICLE WAS TOWED TO REPAIR SHOP WHERE IT WAS DETERMINED THAT THE FUEL PUMP HAD FAILED. *TR
CAR'S ENGINE STOPPED WHILE AT A RED LIGHT. WOULD NOT START AFTER FAILURE. ULTIMATELY, CAUSE WAS DETERMINED TO BE A FAILED FUEL PUMP. I SAW THAT THERE WAS A RECALL ON THE FUEL PUMP FOR 2003 A6 MODELS INCLUDING 3L VEHICLES, BUT NOT FOR 2004 MODELS.]
TL* THE CONTACT OWNS A 2004 AUDI A6. WHEN DRIVING HE SMELLED A STRONG ODOR OF GASOLINE INSIDE OF THE VEHICLE. THE VEHICLE WAS TAKEN TO THE DEALERSHIP WHERE THE CONTACT WAS INFORMED THAT THE ROLL OVER VALVE WAS MALFUNCTIONING, AND THAT THE GAS TANK NEEDED TO BE REPLACED. THERE WERE NO PRIOR WARNINGS. THE CURRENT AND FAILURE MILEAGES WERE 119898. UPDATED 11/18/09. *LJ THE CONSUMER STATED THE SMELL PARTICULARLY STRONG AFTER FILLING UP. THE CONSUMER WAS TOLD HIS VINE WAS NOT INCLUDED IN THE RECALL. UPDATED 11/19/09 THE CONSUMER STATED HE BEGAN TO SMELL GASOLINE INSIDE THE VEHICLE, PARTICULARLY AFTER FILLING HOME. HE TOOK THE VEHICLE TO A SERVICE CENTER AND WHEN THE MECHANIC LIFTED VEHICLE TO INSPECT IT, HE FOUND FUEL LEAKING FROM THE TOP OF THE FUEL TANK ON THE LEFT SIDE, WITHIN INCHES OF THE EXHAUST PIPE. UPDATED 06/08/10.*JB
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