How do you change the oil pressure sending unit on a 1991 S10 2.5L?

To change the oil pressure sending unit on a 1991 S10 2.5L, first ensure the engine is cool and disconnect the battery. Locate the oil pressure sending unit on the engine block, typically near the oil filter; unplug the electrical connector and remove the unit using a socket or wrench. Install the new sending unit, reconnect the electrical connector, and reconnect the battery. Finally, start the engine and check for any leaks.