Does the 2000 BMW 323i have a timing belt or chain?

The 2000 BMW 323i comes standard with a timing chain on the engine. This is better than a belt in my opinion because You should not need to change it during the life of the vehicle. A timing belt is a consumable part that will wear out and needs to be changed every 60,000 to 100,000 miles. A chain on the other hand can last over 300,000 miles. It is still a good idea to check the chain at least once a year though to make sure that it is not loose. If it does become loose it can be a sign of a problem with the tensioner and that will need to be replaced to get it working properly again.