Jeep Liberty 2003 4wd 3.7

[pserrata]

Hello everyone, I am having serius problmes with my Jeep, the engine light came up about a month ago right after I filled up my tank, but according the diagnosis code P0320 this has nothing to do with gas, but the CRANK POSITION SENSOR, which immediately change to a new one, I also put new sparks plugs,this has not resolve the problem, what is happening is that while I drive the jeep’s RPM’S go crazy and the jeep totally stalls(off), then starts again after a hard try…what is going on here? is this electrical? do have something on my fuel tank? help…