What to do if oil pressure drops after changing oil sending unit?
What to do if oil pressure drops after changing oil sending unit? 85 people found this helpful. BTW you will need a screw or a pick to stick down in the oil sending unit hole after it is removed and pick that 2 inch long filter out of the hole. It IS NOT attached to the sending unit. You will have to coax it out. 50 people found this helpful. What happens to oil pressure when you turn off engine? When engine temp starts up, oil pressure slowly falls until "Stop Engine - Low Oil Pressure" warning comes on. Switch...