Oil pressure gauge sticks when cold

[Campinfool]

Only when it is cold my oil pressure will not pop up to a reading. In the morning I will start it up and a minute or two later the guage will pop up to the pressure it always reads. What the hec is this all about??

 

[BrooklynBay]

Your oil pressure sending unit might be bad. It's a cylinder shaped part with a 1/4" NPT male thread, and a stud on top where an electrical connector is pressed on.