Car 1990 Volvo 740 wagon turbo 160k

So over the past 3 months roughly the car has runs fine but a few times over that span of time the car has died. It stumbles then dies, and if you let it set it will restart. I noticed that the times it has died it has been on 1/4 tank of gas or less.

So today the car will not start at all. I drove to work and parked the car. When I went to drive home the car would not start. I checked for spark which it had.

I listened for noise at the intank pump and the main pump and get no sound from either. I checked the fuses 1 and 11 and the fuel pump relay. All the fuses and relays are good.

What I think happened is that my intank pump went out and over time the strain on the main pump killed it too.

Do you all think this is a plausible theory, and if so is there a good way to test the main pump?

(i have a prepump, filter sock, fuel line, and gasket to do in tank pump but still would need to buy main pump. I have been meaning to do intank pump but am intimidated by that whole string maneuver deal).

Thanks in advance,

Chris
Portland, OR