Slugblaster

This code came up and read Crankshaft Pos Sensor Ackt Range Performance
Where is this sensor located and can I find it at my local auto parts because the dodge dealer is closed till tuesday. I was having a surge at around 40 mph and also sometimes when coming to a stop. One day the truck wouldnt start so I drained the water seperator on the air horn but when I opened the drain valve nothing came out but I could hear noise in the line coming from the tank and then the fuel started flowing.I let it flow for a couple minutes and the truck started right up and has since then but I got the check engine light