On my 2002 Ranger Edge, whenever I start it up in the mornings or when it's cold or hasn't been ran, my oil pressure gauge sticks and says I have no oil pressure, but when it gets warmed up or you shut it off and start it back up, it goes back to normal. Anyone know what is causing that?

 

Replace the oil sending unit, common problem.

 

^x2
And take note that it is not a proper reading guage. It is a dummy guage .
It only actuates at about 7 psi , as the 'sending unit' is nothing more than a pressure activated switch.

 

^ X3 on that.

Common Ranger issue. I replaced it on the 01 as well.