The Audi A6 was first introduced back in 1994 as a refreshed version of the Audi 100. Since then, the A6 model has spanned 5 different generations and is now one of the most popular and best sold Audi models out there. The current Audi A6 C8 is only 2-3 years old and is shaping up to be another success for the luxury automaker from Ingolstadt.
Not all A6 generations are equally as reliable because the C6 seems to be the best one of the bunch. The C7 takes second place while the new C8 is now third when it comes to reliability. However, the C8 is only at the beginning of its lifeline, so it’s understandable to think that the upcoming C8 refresh is going to solve many problems that plague the current C8 A6.
Either way, the most common Audi A6 problems are excessive oil consumption, timing chain issues, carbon build-up issues, gearbox issues, and electrical issues. In order for an A6 to last a long time, it needs constant maintenance, without it, it is likely going to cause all sorts of issues.
That’s the reality of German executive luxury cars as they are not designed to withstand lackluster maintenance. It is not true that these cars are not built well enough, it’s rather the fact that many people who buy them don’t maintain them adequately.
Audi A6 excessive oil consumption issues
Many European luxury cars are known to drink too much oil, especially after accumulating a decent amount of miles on the odometer. Issues such as these can be solved in two different ways because the most common reasons why this happens is because the oil is leaking or because the engine is fairly worn out.
If the oil is leaking you can either keep refiling the oil tank whenever the oil levels drop, but it is a better idea for you to find the root cause and solve it. If the A6 model you are looking at is older and has a fair bit of miles on the clock, the car needs to guzzle increased amounts of oil in order to lubricate itself properly.
Audi A6 timing chain issues
One of the most dreaded issues that plague the A6 are issues with the timing system, more specifically the timing chain tensioner. The best Audi A6 engines are V6 and V8 engines, and both of these use sophisticated plastic guides and hydraulic pistons for the chains to keep them nice and tight. However, these are known to fail, and when they do, you need to act fast.
You need to act fast because your entire engine might be in danger. If the tensioner fails, the chain can possibly even destroy the entire engine in just a few hundred miles, or even less. Be sure to pay close attention to these plastic tensioners if you are in the market for an A6.
Audi A6 carbon build-up issues
Many of the engines found in the A6 rely on the direct injection system to sprinkle fuel directly into the cylinders. The upsides of this technology are that direct injection engines use less fuel and they emit less CO2 while making more power in the process. This is vital for many modern automakers as technologies such as these enable them to still make larger engines that pass CO2 emissions testing.
However, the direct injection technology causes excessive carbon to build up in the intake valves. If these carbon deposits accumulate too much, they are likely to limit the airflow to the engine which tends to cause rough idling, misfires, stalling, and reduced power. The easiest way to solve this is to either change the oil more frequently or clean the deposits regularly.
Audi A6 gearbox issues
The Audi A6 is available with either a manual, a Tiptronic torque converter, an S-Tronic gearbox, or the dreaded Multitronic gearbox. The Multitronic CVT transmission is commonly being used on FWD Audi models and is known to fail often.
The easiest way to take care of Multitronic issues is to flush the transmission oil every 35,000 miles, otherwise, the gearbox is likely to fail.
Audi A6 electrical issues
Older German luxury cars are no strangers to all sorts of electrical issues, and it’s the very same story with older A6 models. These issues manifest in many different areas such as the in-car electricals such as power windows, phone connectivity, GPS, exterior lightning, power trunk lid, and so on.
These can easily be solved, but they often reappear, especially on older Audi models.
What is the least reliable Audi A6 model?
There are a few Audi A6 models years that are simply too problematic and should be avoided. These typically experience all of the issues listed in this article, and many more, so they are able to rack up maintenance and repair costs faster than more dependable Audi A6 models.
You should avoid the 2000, 2003, 2004, 2005, 2006, 2011, 2013, 2014, 2015, 2016, and 2019 models. The common rule of thumb is to always look for newer models from a certain generation which means that post-facelift A6 models are always your best bet when it comes to reliability.
Which Audi A6 models are the most expensive to maintain?
The Audi A6 is a through and through luxury car available with large engines, lots of power, and lots of technology. All of these need proper maintenance, and some models are way more expensive than others. The most expensive Audi A6 models are the sporty S6 and RS6 models, especially those with a V10 Lamborghini-derived engine.
Audi A6 models with the dreaded Multitronic CVT gearbox are also known to be expensive to maintain, and it’s the same story with older Audi models with the Quattro AWD system.
Is the Audi A6 worth it?
The Audi A6 is one of the best mid-size luxury sedans of all time, and as such, it is indeed worth it. However, if you are in the market for an A6, you need to choose the right car which means that you need to be able to always keep aside a certain amount of money for maintenance costs.
An A6 is not a Toyota Corolla which means that it is way more complex and needs more delicate care. While shopping for an A6, always go for post-facelift models, and try to avoid the Multitronic gearbox. Cars with many miles on the clock are not necessarily bad because the worst Audi A6 models are those that have not been maintained according to the Audi maintenance schedule and recommendations book.