Even though they are marketed as such, timing chains do not last forever. They can fail in a number of ways including a complete break causing the engine to stop, or a stretch causing the engine to skip time. We have seen timing chain issues on every engine that Volkswagen and Audi have ever made. There is no one engine that escapes it.
timing chains on a 24v VR6 engine
Timing chain failure may cause the engine to run incorrectly, the ‘check engine’ light may come on, or it may cause the engine to stop running completely. Sometimes there is no damage and the repair work includes simply installing a new chain and the related components. Other times there is cylinder head damage, valve damage, and or piston damage.
We have seen more timing chain failures in four cylinder engines than in six and eight cylinder and as such we recommend Volkswagens and Audis with four cylinder engines be inspected, as preventive maintenance, at 125,000 miles and, if necessary, the timing chains replaced.