The temp gauge in my 93 Dakota 3.9 stopped working. So, how do I fix it? My oil pressure gauge stopped working, and after a few minutes of checking I noticed that the sensor plug had fell off. Could it be something that simple? (I hope) Thanks for the assistance

 

Could be. Its one of the two small sensors where the upper radiator hose goes into the intake. i think its the single wire one.
If thats not it, get a new sensor, or use a meter to check the guage itself.