I need to have the truck smogged soon, while I have the engine cover off I want to replace the oil pressure switch and the knock sensor. I haven’t had an oil pressure gauge for some months, And I keep getting a check engine soon light, pulling the code yields 43, which is “faulty reading from a knock sensor” or something.

I have the knock sensor, I need to pick up an oil pressure sensor, I see them advertised as either 1 terminal or 3 terminal. I’d rather have it in hand than need to go buy one after I get the cover off. Anybody know which is needed?