Explorer 1998 4.0L oil pressure drop

[mikeymm]

I have this Explorer for the last few days it is doing strange things. When it is cold started the oil pressure gage stays in the center position on the display after few minutes of driving if I break the oil pressure drops to zero, the guage arm starts to shake and the "check guage" light comes on. But when I accelerate from a stop the oil pressure goes up to the center position like normal and the "check gauge" light disappears. I also notice some sound coming from the engine while its idling in drive position and seems to go away once the oil pressure gauge goes back to normal. Please help with some ideas? Thanks:

 

[BrooklynBay]

Welcome to this forum! It could be a defective oil pump.

 

[Exploderpilot]

Sounds like a hurt motor. I would get it looked at real soon, as those symptoms are the same as when my old suburban died....

 

[dfb]

At first I was thinking the sending unit...But when you mention the sound of the engine, it's UH OH.....My guess is a cracked pickup tube for the oil pump....