oil pressure bouncing

[WSex]

my oil pressure is bouncing at warm idle on a mechanical gauge.

[WildBillyT]

Where is the gauge hooked up? Oil level OK? No leaks? Line purged?

[WSex]

Where is the gauge hooked up? Oil level OK? No leaks? Line purged?

the plate above the oil filter.
oil level is ok. the electronic one also bounces.

[LTb1ow]

Oil pump O ring on pickup.