Timing chain, belt or tensioner failure on the 2002 Audi A6
Only 4 reports for this mode came with an odometer reading, which is too few for percentiles to mean anything. The page is here because someone linked to it; treat the figures as anecdotes, and see the full report for this year instead.
When timing chain, belt or tensioner failure gets reported
There are 4 reports of timing chain, belt or tensioner failure on the 2002 Audi A6, 4 with a mileage attached. That is too few to place the failure on the odometer with any confidence.
A part like this is normally expected to survive 120,000 miles. It is the 8th most-reported problem on this model year.
The whole distribution
| 10th | 25th | Median | 75th | 90th |
|---|---|---|---|---|
| — | — | 65,500 miles | — | — |
Read the 10th percentile as “one report in ten arrived this early”. Exact figures are shown in this table because it is the table of record; everywhere else on the site they are rounded to the precision the sample can carry.
What a percentile can and cannot tell you here
These five numbers describe the readings owners gave, in order. The median is the middle one: half the reports arrived below it. The 10th and 90th are the edges of the bulk of the distribution, and the distance between them is the part worth reading. A tight spread — say 70,000 to 95,000 miles — points at something that wears out on a schedule, and the schedule is knowable. A wide one, 20,000 to 190,000, points at a fault that hits some cars and never troubles others, which means the mileage on the listing in front of you tells you very little about your odds.
What these figures are not is a survival curve. Every reading here comes from a car whose owner filed a complaint, so the sample contains only failures: it cannot say what share of the fleet made it past 150,000 miles untouched, because those owners had nothing to report. Nor is the mileage the moment of failure — it is the odometer reading as recalled at the time of filing, which may be weeks later and is sometimes rounded to the nearest ten thousand by the person typing it.
Percentiles are shown at all only once 8 readings exist for the vehicle and mode. Below that the middle of a handful of numbers is noise wearing a decimal point, so the figures are withheld rather than dressed up.
What happens, and what it costs
Putting it right typically runs $1,200–$4,500 at an independent US shop. That range is an editorial estimate held in this site's failure-mode catalogue, not a figure from NHTSA, and it is a repair cost rather than a diagnosis cost.
This mode is classified as critical, which means a failure can leave the car unable to stop, steer, or stay out of the way of traffic. It is weighted accordingly in the risk score.
The same failure on other years
The same failure is reported on 4 model years of this car. It shows up earliest on the 2000, at a median of 50,000 miles, and latest on the 2012 at 120,000 miles.
By volume the 1999 carries the most reports, with 9; the 2002 has 4. A mode that appears across most years of a model is usually a design choice rather than a bad batch.
If one year stands out to the left, that is the year to avoid; if the whole line sits at a similar mileage, this is wear rather than a defect in one production run.
Tick median reported mileage Solid middle half of reports Faint 10th to 90th percentile Colour how bad the failure is when it happens
What owners wrote
Verbatim from NHTSA complaint narratives, trimmed for length. The mileage is the one the owner gave.
Audi a6 3.0 2005 68,000 mi. Premature water pump failure premature timing belt failure as I was pulling into a shopping center parking spot on 4/25/05, the car began to feel different and the power steering was not working. I shut car off immediately and it was steaming. I turned key on again without starting engine in order to check guages. There was no indication of overheating. Outside the car the coolant had leaked onto the ground. I had it towed by flatbed to winner audi in wilmington, de. They diagnosed that water pump failed and resulted in timing belt failure, also. Quoted $2380.00 to repair the timing belt and water pump. Once this is completed, further diagnostics are required to determine if more damage exists. Service advisor, michelle suggested I call audi for assistance. She said that sometimes they will agree to have the repair done for the customer at the warranty rate, which is half the regular rate. I contacted audi america customer relations @ 800-822-2834 for assistance. Willie moore took my information and indicated that even though the vehicle was out of warranty, he would review the problem with the dealer…
My engine failed while driving at 35 MPH on route 375 in woodstock, ny. The failure was a result of assembly bolts on the reverse side of the exhaust cam shaft variable valve timing sprocket loosening and falling out against the cylinder head, stalling the the camshaft and breaking the timing belt. Inspection of bolts show neither a lock washer or thread lock adhesive were present to prevent the loosening due to heating and cooling or vibration. Further service of bolts cannot be performed as there are no tightening specification for these bolts. An easy fix for this mechanical failure would be to remove both valve covers and replace the bolts on the timing gear sprockets with new bolts with adhesive on the threads. This is an interference engine, which results in a catastrophic failure in the bending of valves and total engine destruction. *tr
2002 audi a6 with a belt failure. Consumer states that he did research about this failure and found out other people have had the problem too. He stated that when the water pump and thermostat was replaced or fixed the timing belt was not. *kb the consumer stated his engine overheated and smoke began to emit from the engine. The consumer was informed the water pump to the coolant wasn't functioning properly. Prior to the incident, the check engine light illuminated, faulty coils were replaced and the vehicle had a leaking coolant bottle. *jb
Also reported on the 2002 Audi A6
Other engine problem
Other electrical problem
Seat belt or retractor failure
Other speed control problem
Misfire or rough idle
Fuel leak or fuel odor
How far this goes
This page is kept out of search results because 4 reports is not enough to publish percentiles from. It stays reachable because somebody looking at this exact car would rather see the reports than be told there are none.
Complaints are voluntary, so 4 is a floor and not a count of affected cars. Mileages are typed in by owners and cluster on round numbers. And the mode itself is assigned by software reading the complaint text, which is reliable in bulk and fallible one report at a time.
Questions this page answers
At what mileage does timing chain, belt or tensioner failure happen on the 2002 Audi A6?
Across 4 owner reports that included an odometer reading, half were filed by 65,000 miles. A quarter were filed before — and a quarter after —. These are the mileages owners reported when they complained, not a prediction for any individual car.
How common is timing chain, belt or tensioner failure on the 2002 Audi A6?
4 reports have been filed with NHTSA, about 0.4 per 1,000 vehicles. Complaints are voluntary, so this is a floor rather than a count of affected cars.
What this is and is not. These are the mileages at which owners chose to complain to a federal agency, which is not the same as the mileage at which the part fails on every car. It skews toward failures that happened outside warranty, cost real money, or frightened someone. It is still the only public dataset that carries failure mileage at all, and the shape of a few hundred readings is informative even when a single one is not. Methodology · JSON · this failure on other cars
Source Owner complaints and recall records published by the US National Highway Traffic Safety Administration, model years 1996–2027 Figures rebuilt Published by AtWhatMileage How every figure is computed