Squeaky engine

[Blanco92]

Iv heard a few VAG cars with the problem when on full lock and it is the pulley on the alternator, but think it only happens when on full lock?

It also (or at least it does on Audi TDIs) makes the car rattly on tickover, however that's only with the pulley is completely knackered. On my dad's VW TDI it didn't have the rattly tickover, though it did have the squeeling from the pulley and the vibrating poly V belt.