Like 10 years ago or so, I also worked on engine control units with inductive crank sensors. It's however not so difficult to get that kind of signal from a 5V signal. Yo don't actually need the sine form, just the shape of the gap has to be adapted (symmetric transition in the gap) and you need a bipolar signal. When I was lazy, I just used a max232 to convert the (inverted) 5V signal to a +/-9V volt signal.