Similar to adding back a sound, one of the problem areas Toyotas had with unintended acceleration - and the only one that was "repaired" with the recall - was the mechanism to add resistance back in to the throttle-by-wire accelerator pedal. It could potentially engage too deeply and be sticky, so they added metal nuggets to limit the travel of the mechanism (just the resistance component, not the whole pedal). So something designed to make the pedal "feel" right had the potential to kill people. Just great!
(But it turned out it was likely solely driver error anyway.)