I've had terrible luck with sensors and other electrical parts from Crapa. At the shop I worked at, that's where my boss ordered from.Cheap discount parts store sensors often go bad in a year or don't perform correctly. I used a crank sensor from NAPA once to fix a Jeep Grand Cherokee, after the sensor had been previously replaced by a repair shop. They are located under the exhaust manifold/crossover pipe and are subjected to a lot of heat. It has a coil in it, so that is why they go bad when exposed to high heat for a long time. The crank sensors on these 4th gen vans just push right into a hole on the bellhousing, with no need for a paper spacer. Hopefully you just need a new crank sensor (Mopar or NAPA).
One time a Chevy pickup came in throwing a code for the crank sensor. We got a new one from Crapa. The truck wouldn't even start with the new sensor installed. It drove in on the old one. I yanked a used sensor off an old engine that was waiting to be scrapped, put it in, and sent the guy on his way.