Vacuum leak question
 

Does anyone have DIY photos and explainations to where to look for vacuum leaks? I have W140 '99 S500

Thanks

Why do you ask?

The general answer to your general question is;

All places that contain vacuum or are exposed in some way to vacuum or where vacuum is present.

Places like vacuum hoses, manifold gaskets, sealing O rings on the injectors and injector holders, aux air lines, brake boosters, transmission modulator valves, intake manifold seals, any plumbing connected to the intake manifold, vacuum operated devices such as climate control actuators, and the list goes on. Think of it as a game of hide and seek.

Look at all the components and ask yourself the question "Is there vacuum associated with this thing?" if the answer is yes - start checking for leaks.