Why doesn't Volkswagen use timing chains?

[McElias]

Volkswagen vehicles do not use timing chains because they have drawbacks. As they gradually stretch with use, they can produce noise, unlike timing belts which are more convenient to replace every approximately 100,000 kilometers, with lower costs, and the engine won't suffer from excessive noise as a result. The functions of the timing belt and water pump drive are as follows: Function of the timing belt: The main function of the engine timing belt is to drive the engine's valve train, ensuring that the intake and exhaust valves open or close at the appropriate times to allow the engine cylinders to properly intake and exhaust air. Function of the water pump drive: In some models, such as the Volkswagen Jetta (fuel-injected), Santana 2000, Bora, Audi, etc., the timing belt also takes on the task of driving the water pump.