Location of oil pressure switch on a 2001 buick century

SOURCE: Where is the fuel filter located for Buick Century 2001

The fuel filter is located underneath the car in front of the gas tank.
You have release the fuel pressure. Remove the fuel filler cap, locate the fuel test port on the fuel rail on the passenger side on the end of the right real fuel rail for a 3.1L engine.
3.8L engine yhr test port is located at the pressure regulator under the trim cover.

SOURCE: Radiator Plug Location

It should be on the right lower side of the radiator when looking at the engine .

SOURCE: 1994 buick regal

More than likely (and we will hope) it is the oil sending unit. In comparison it is a very cheap and quick fix to replacing the oil pump. Auto Zone has a pretty good componet location section that has tips for replacement if you cant find the sending unit or the oil pump. Try that first it may save you a lot of work.

SOURCE: 2001 Buick Century shift solenoid

It is in the side cover on the valve body. The transmission needs to be removed to access the solenoids.

SOURCE: OIl PRESSURE SWITCH

The oil pressure switch is located next to the oil filter