It is a K jetronic system that is electromechanical with an ECU. What you're looking at is the fuel distributor injection plate that is not tied to the throttle, air going past it opens it and causes the fuel distributor to send more fuel to the injectors. Check the pump in the back, under the car right outside the tank.
The only things correct about that statement are the last sentence and the words K-Jetronic. Everything else is slightly off. Firstly, there's no ECU. Secondly, the throttle plate in front of the fuel distributor is absolutely tied to the gas pedal. Sounds to me like it's simply stuck, that is to say, either the throttle plate itself is stuck or the linkage is stuck (the latter is more likely, in my opinion).
Now, as to the no-start condition. Yes, the fuel pump is right behind the right rear wheel, in a housing together with the fuel filter. With an assistant working the ignition switch, get under there and listen for the pump to whir and/or feel for it vibrating. If neither is taking place, check for voltage at the pump terminals. If there's voltage, the pump itself has failed, if not, proceed further "upstream". Now your suspects are the fuel pump relay and the ignition switch. The fuel pump relay is pretty inexpensive.
So, check the throttle linkage for free movement, the check the pump and report back.
Also, we have a dedicated W116 forum.