For servicing or repairing the Oil Pressure Switch, the needed tools would include: Oil Pressure Switch socket (J 41712). Start by removing the engine cover and the air cleaner assembly. Shut off the connector from the engine oil pressure gauge sensor, then use a wrench to hold the engine oil pressure gauge sensor fitting with a wrench and recorded it before detaching. Pull out the engine oil pressure gauge sensor using the Oil Pressure Switch socket (J 41712), and if required, extract the engine Oil Pressure Switch fitting. Seal gm p/n 12346004 or equivalent to the threads of the engine Oil Pressure Switch fitting, do not loosen it after the initial torque. Fit the engine oil pressure gauge sensor fitting and tighten with no rotation beyond 359° after torquing to 15 nm (15 inch lbs.). Rotate the engine Oil Pressure Switch fitting to the proper position by rotating it clockwise to 50° from the centerline after which the Oil Pressure Switch would be installed. For some reason, hold the Oil Pressure Switch fitting using a wrench and tighten the Oil Pressure Switch to 30 nm (22 ft. Lbs.) using the Oil Pressure Switch socket (J 41712). Lastly, connect the electronic connector, and replace the engine cover and air cleaner assembly.