fuel pump on 1990 Mercedes-Benz 190E

How can you test the fuel pump to know if is that or one of the other parts associated with fuel delivery.

Asked by for the 1990 Mercedes-Benz 190E
you must have some basic items, such as a fuel pressure
gauge. an experienced MB tech is worth his weight in gold because if the fuel distributor is the problem, that part alone costs more than the whole car is worth.
1 more answer
It is simple according to a You Tube video. REmove the breather to get to the injector housing and the incoming fuel line. Turn car on until you no longer hear the fuel pump or long enough to build fuel pressure. Barely crack the fuel line if you have spray at line break fuel pump is working