- We have seen a couple of single link timing chains on A12's before. Wierd. Insist on the factory specified double-chain
- A rattle can be the trait of a stretched timing chain. Pinging/pinking has also often been mistaken for timing chain rattle
A-series engine has a short timing chain -- and with an automatic adjuster -- it rarely stretches or goes bad.
Compare to the loooooong chaing used in the Nissan KA24E engine: