They are doing like trully hunters killers... and want drain the battery or the O2 of the boat until it was forced to surface. or stay forever underwater
If they don´t return to home the only option is wait to the night and run or fight in surface.
Or show the periscope near of a DD, with some luck Perhaps they blow up each other with the guns.
In a diesel submarine with all of movile parts like turbines, ventilation, compressors and pumps shut off, coul be almost undetectable at 0 knts with pasive systems.
the question is how many things need to run a WW2 submarine, i think that a very few...perhaps ventilation fans and no more.
the only noise could be the hull in the surface waves or depht pressure effects.
In the later war the only hope was the new XXI sub , with great underwater endurance, speed, and snorchel.
Today the AIP in the modern diesel subs and radar coating snorchels make they a very dangerous oponent despite the advanced ASW gears and tactics.