Problems · NHTSA complaints
2004 Audi S4 problems
Owners filed 29 complaints about the 2004 Audi S4 with NHTSA between Jan 2007 and Jul 2018. The most-cited component is engine and engine cooling (12).
Complaints
29
Filed with NHTSA
Crashes
0
Reported by owners
Fires
1
Reported by owners
Injuries
0
People reported injured
Deaths
0
Reported to NHTSA
Complaints by component
One complaint can cite several components
- Engine and engine cooling12
- Power train5
- Engine3
- Exterior lighting3
- Visibility3
- Electrical system2
- Steering2
- Tires1
- Service brakes, hydraulic1
- Structure1
- Seat belts1
- Vehicle speed control1
- Air bags1
- Other / unknown1
Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.
Data from NHTSA Complaints API · synced Oct 30, 2026NHTSA vehicle page
When complaints were filed
Does it get worse with age? Complaints per calendar year filed
3
0
14
3
0
3
0
2
1
1
1
1
View as table
| Model year | Complaints filed per calendar year |
|---|---|
| 2007 | 3 |
| 2008 | 0 |
| 2009 | 14 |
| 2010 | 3 |
| 2011 | 0 |
| 2012 | 3 |
| 2013 | 0 |
| 2014 | 2 |
| 2015 | 1 |
| 2016 | 1 |
| 2017 | 1 |
| 2018 | 1 |
Mileage at failure isn’t a structured field in NHTSA complaint data, so we don’t chart it. Some owners mention it in their reports below.
Top problems in owners’ words
Verbatim from NHTSA complaints, newest first
Engine and engine cooling
12 reports
“2004 AUDI S4. CONSUMER STATES VEHICLE FAILED WHILE DRIVING, ENGINE, POWER BRAKES AND STEERING LOCKED UP *TGW THE DEALER INFORMED THE CONSUMER, THE VEHICLE HAD SUFFERED CATASTROPHIC ENGINE FAILURE, WHICH WAS MOST LIKELY DUE TO THE FAILURE OF THE TIMING CHAIN OR ADJUSTERS. THE CONSUMER WAS QUOTED A PRICE OF $24,000 FOR THE REPAIRS. THE CONSUMER HAS SINCE LEARNED IT WAS A RELATIVELY COMMON PROBLEM FOR HIS MODEL AND YEAR. THE SPECIFIC MECHANICAL FLAW SEEMED TO BE THAT THE TIMING CHAIN COORDINATED THE ACTION BETWEEN THE PISTONS AND THE VALVES. THE TIMING CHAIN WAS SUPPORTED BY SEVERAL PLASTIC GUIDES. THE GUIDES PUSHED AGAINST THE CHAIN BY THE ADJUSTERS. *JB”
Power train
5 reports
“AUDI CLAIMS THAT THE TIMING CHAIN ON THOSE VEHICLES ARE LIFETIME AND DOES NOT NEED TO BE SERVICE. UNFORTUNATE THE TIMING CHANGE TENSIONERS ARE MADE OF PLASTIC WHICH THE WEAR OUT AT ABOUT 50K MILES, CAUSING A START UP RATTLE AND EVENTUALLY ENGINE EXPLOSION FROM THE CHAIN COMING OF THE GUIDES AND DESTROYING THE ENTIRE ENGINE AND CAUSING A MASSIVE ACCIDENT AT HIGH SPEED. HUNDREDS OF PROBLEMS LIKE THIS ONE ARE REPORTED ONLINE FROM THOUSANDS OF PEOPLE EVEN YOUTUBE VIDEOS. NOT TO MENTION THAT EVERY TIME YOU BRING YOUR VEHICLE AND COMPLAINT TO AUDI THE CLAIM THAT THE RATTLE IS NORMAL; JUST TO FIND OUT THAT IS THE FIRST CLUE OF FUTURE ENGINE FAILURE. *TR”
Engine
3 reports
“AFTER ENGINE COOLS DOWN, TIMING CHAIN RATTLE CAN BE HEARD UPON STARTING THE CAR. CHAIN RATTLE MEANS THAT PLASTIC GUIDES OR ADJUSTERS ARE WORN, AND MIGHT GO ANY SECOND. SPOKE WITH AUDI REP ONLINE, WHICH ADVISES ME THAT THIS IS NORMAL, AND EXPECTED. KNOWING BASICS OF ENGINES AND TRANSMISSION, I DIDN'T BELIEVE THAT SOMETHING IS "LIFE TIME" AND IS NOT SERVICEABLE, ESPECIALLY IF IT'S PLASTIC (WHICH TENDS TO SHRINK AND EXPAND DEPENDING ON TEMPERATURES, AND THEN HAS FRACTURES WHICH SNAPS). TWO DIFFERENT INDEPENDENT LICENSED AUDI SHOPS CONFIRMED THAT THE GUIDES AND ADJUSTERS HAS TO BE REPLACED IN ORDER TO PREVENT CATASTROPHIC ENGINE FAILURE. CHAIN SKIPPING A TOOTH MIGHT MEAN BENT VALVES, SCORED CYLINDER WALLS AND THE LIST GOES ON. WHAT IS LIFETIME, SHOULD BE COVERED BY AUDI. IF IT'S PROMISED TO BE LIFETIME AND NEEDS NO SERVICE, SHOULDN'T BREAK. IF IT BREAKS THAT ONLY MEANS DESIGN FLAWS, WHICH ARE OBVIOUS IN THIS ENGINE. YES, CAR ISN'T NEW, BUT THE PARTS WERE LIFETIME, SO I'M EXPECTING THEM TO LAST UNTIL ENGINE IS WORN OUT, NOT THE PARTS THAT ARE LIFETIME. IF NHTSA WILL DO FULL SCALE INVESTIGATION. WILL BE OBVIOUS THAT LARGE AMOUNT OF S4'S RANGING FROM 2004 TO 2007 ARE…”
Exterior lighting
3 reports1 fire1 related recall
“XENON HEADLAMPS WIRING ALL CORRODED AND BARE WITH NO INSULATION LEFT. CHECK WITH AUDI AND THEY SAID OUR VEHICLE AND VIN IS NOT PART OF ANY RECALL. YET RCORRD-05V096-4498 IN YOUR DATABASE SHOWS A MOFIFICATION LETTER FROM VW TO INCLUDE OUR VIN. THERE IS NO RECORD ACCORDING TO AUDI SERVICE SHOPS THAT SHOW ANY RECALL WORK DONE TO OUR HEADLIGHTS. I HAVE ATTACHED A PICTURE THAT SHOWS THE DETERIATION OF THE ELECTRICAL WIRING AND HEADLAMPS TO OUR 2004 AUDI S4. WOULD APPRECIATE SOME ASSISTANCE TO HAVING OUR HEADLAMPS REPLACED FOR SAFETY REASONS.”
Visibility
3 reports
“2004 S4 WIPERS STOP WORKING (STOP IN THE MIDDLE OF WINDSHIELD) IN RAIN, MOTOR WORKS SEEMS AS SOMETHING SIZED, IN SOME SITUATIONS MAY CAUSE BIG DAMAGE AND INJURY. *TR”
Electrical system
2 reports1 fire
“TL* THE CONTACT OWNS A 2004 AUDI S4. WHILE DRIVING AT NIGHT, THE LOW BEAM HEAD LAMPS FAILED TO ILLUMINATE WITHOUT WARNING. WHILE ATTEMPTING TO THE HEAD LAMP BULBS, THE CONTACT NOTICED THAT THE WIRING WAS BURNED AND DAMAGED. THE DEALER AND THE MANUFACTURER WERE NOTIFIED OF THE FAILURE, BUT THE VIN WAS NOT INCLUDED IN ANY RECALLS. THE APPROXIMATE FAILURE MILEAGE WAS 79,000.”
Data from NHTSA Complaints API (owner reports, unverified) · synced Oct 30, 2026
Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.