I know even the ones that use the exp valve would usually still be a cylcling clutch system. They used thermostatic switches on some and pressure switches in the low side on some that would cycle the comp. From what I remember most all of the Dakota's through the 90's used a cycling comp system. They dont have an EPR valve or Suction Throttle Valve on them so they still cycle the comp to keep the evap from freezing. It sounds as if its still low but as was said installing gauges will tell you alot as you can tell by the head pressure as per the temp and humidity outside if its about a full charge. Ron