Fuel to engine problem Audi 80 Sport 84'

[80sport_owner]

Hello,
I am experiencing problems with my Audi 80 sport (1984)
Recently my car has been stalling due to what seems to be a lack of fuel getting to the engine. I have tried changing the fuel filter and clearing out some of the crap that's in the plastic reservoir near the electronic fuel pump. (sorry about my lack of knowledge coming out in my writing)

Basically what happens is: I turn the ignition over and can hear the pump working and the relay ticks twice indicating it seems to be working. I will then be driving along and the fuel pump starts making a loud struggling noise then i start to feel the engine stalling with lack of fuel.

Any ideas to answer my probably dumb ass question?

Thanks,
Mark