1992 Volkswagen Jetta Fuel pump

My manual states it this way: "The injection pump is driven at half crankshaft speed by the camshaft timing belt. Fuel is drawn from the fuel tank, through the filter by the injection pump, which then distributes the fuel under very high pressure to the injectors via separate delivery lines."
So, no fuel pump like what you might be used to. Sounds more like you may have an injection pump problem.
To R & R the injection pump, you would have to be familiar with TDC procedures, timing belt installation etc. If you're not, better look for a qualified mechanic.