91 Plymouth Acclaim won't start

2 days ago after stopping to get gas my car wouldn't start. When I turn the key and the starter should be turning the engine nothing happens. I checked the engine codes and got 15, which indicates a bad distance-speed sensor, but that had been replaced with a new one from the dealership no more than 500 miles earlier. In any case we replaced the distance-speed sensor with a used one from a junkyard, with no effect. Thinking it might be the neutral safety switch we replaced that as well, with no effect.

Does anyone have any other ideas for what could be preventing it from starting?

Edit: If it's relevant, it's a 4cyl 3 speed automatic non-turbo, also the speedometer would occasionally stick before the distance-speed sensor was first replaced, which prompted replacing it in the first place

Edit 2: We replaced the Starter and it works fine now