Means your engine oil pressure is low due to faulty oil pressure sensor which is located on top or the oil filter housing. It could also mean low on engine oil due to a leak in the engine somewhere or past due oil changed. It could also mean a faulty oil pump, weak oil pump, or restricted oil passage due to sludge.
Here is the procedure for testing for oil pressure, which lists the possible causes of the pressure light coming on.
The following can cause low or no oil pressure:
1.Low oil level -- fill to the full mark on the oil level indicator.
2.Incorrect or malfunctioning oil pressure Switch -- replace the oil pressure switch.
3.Incorrect or malfunctioning oil pressure gauge -- replace the oil pressure gauge.
4.Improper oil viscosity or diluted oil Install oil of proper viscosity for expected temperature.Install new oil if it is diluted.
5.The oil pump is worn or dirty -- clean or replace the oil pump.
6.The oil filter is plugged -- replace the oil filter.
7.The oil pickup screen is loose or plugged -- replace the oil pickup screen.
8.A hole in the oil pickup tube -- replace the oil pickup tube.
9.Excessive bearing clearance -- replace the bearings.Cracked, porous, or plugged oil galleries -- repair or replace the engine block.
10.The gallery plugs are missing or improperly installed -- install or repair as necessary.
11.The pressure regulator
valve is stuck.Check the pressure regulator valve for sticking in the bore.Check the bore for scoring and burrs.
12.The camshaft is worn or poorly machined -- replace the camshaft.
13.Worn valve guides -- repair as needed.
If the vehicle has low oil pressure perform the following tests.
Check the oil level.
Raise the vehicle and remove the oil filter.
the engine and check the overall oil pressure, the oil pressure switch,
and for noisy lifters.
The engine should be at operating temperature
before checking the oil pressure. The oil pressure should be
approximately 414 kPa (60 psi) at 1,850 RPM using 5W-30 engine oil.
If adequate oil pressure is indicated, check the oil pressure switch.
a low reading is indicated, press the valve on the tester base to
isolate the oil pump and/or its components from the lubricating system.
An adequate reading at this time indicates a good pump and the previous
low pressure was due to worn bearings, etc. A low reading while
pressing the valve would indicate a faulty pump.
the tools to test the pressure, about all I might suggest is trying
another oil filter brand, to see if you can get more pressure. It
sounds like the sensor is working properly.Please let me know what you find out. Keep me posted and be glad to help you get your Montana running 100%. please rate. Oil pressure test kit J 25078-c is needed to test the oil pressure and can be loaned out in most auto parts store like Auto Zone or Parts Source.