Chances are if you have over 100k miles your timing chain may have slipped. Those did have some problems with stretching especially if the oil wasn’t changed regularly. It’s not hard to pull the valve cover and see if it’s tight or if it’s loose. I don’t believe those are interference engines and if you can still turn it over I would guess not. If your timing chain is tight then your looking at something in the wiring harness or PCM/ECM. It’s possible the sensor ring on the crank might be having problems but usually unless it’s had work done it that area or something like serpentine belt breaking and wrapping around the pulley those don’t go bad. One other thing you could do is check the connector first on the crank sensor. Is it dark or corroded maybe it’s not making a good connection?