92 vw passat fuel pumps issue

Hi I have a 92 passat with 65000 miles. The cars original owner let it sit for along time. Issue is It has an in tank transfer pump and an under body main pump. I replaced both pumps already but now the underbody pump buzzes like a sworm of bees. when the car was running as I pressed the brakes the pump whined louder. But now I’ve noticed the whining is louder and the cars shuts off. And its hard to restart. I’ve chaged the fuel pump relay and still it shuts off. What can I do? Helpppppp… thanks… rico…

Have you changed the fuel filter? If “yes”, change it again. Next thing to do is measure the fuel pressure at the injector log to see if it is up to specification with the engine ‘off’; with the engine running; and with the engine running and the brake pedal pressed.