99 oil pressure drops below 3psi at idle

[Floyd4runner]

What are common issues I can check before I pull the pan?
I know the gauge on the dash isn't accurate, I put a mechanical gauge and at least I know the gauge is telling me I have a problem.
I've had this pickup for 20 years, 362k, great truck, runs perfect, looks better.
Thanks guys

 

[Turbo Terry]

My 99 did that also. Dropped to zero. Started dinging. I knew a still had oil pressure at 65 miles a hour you wouldn’t barely get to the side of the road before serious engine damage. It was the sensor. Kind of a harder place to change out. Requires a bigger than normal socket as I recall. Also the prices for the sensor are all over the map. Shop for a good quality one. Also consider putting a real oil pressure gauge to the top of the oil filter etc. All I know about this good luck

 

[BigPapa]

I put a mechanical gauge and at least I know the gauge is telling me I have a problem.

So, with the mechanical gauge, did the pressure fall to 3psi? Where is the tube installed at?

 

[Tuesdak]

I assume the mechanical gauge is somewhat accurate and confirming the low oil pressure sensor tripping a warning.

Pull the oil filter and inspect it for signs of coming apart. Before you Cut It Open make sure it's not the cause of the engine failure as the filter company may owe you an engine. If you cut it open, preferably without a hacksaw, look for metal shavings. With a possible filter failure warranty claim: It's better to send an oil sample out: overnight the sample depending on how bad you need the truck. Looking for fuel, coolant, also loss of viscosity.

Change the oil. Unless you parked it to wait for the results from the oil sample. Parking it NOW is the difference between engine replacement from rod through the side of the block and rebuildable.

Then if the problem continues with nothing outstanding in the oil sample look at the pressure relief and regulator around the oil cooler. Then oil pump including gasket failure for oil pump to block.

 

[Ozymandias]

Also check the pressure regulator for proper function.

Nothing inside the pan to check for.