[shadowgray396]

It could be an exhaust leak and as the engine warms up it will go away. My oil presuure goes up and down more that I have 125k on my pickup I have noticed. It could be a sending unit, but could also be your oil pump showing some wear on it. Putting a oil pressure guage on it and checking it that way would tell you if your sending unit is going bad. If the pump is worn the pressure at idle will go down.