All Toyota models secure the oil pump inside the oil pan. The oil pump delivers oil from the oil pan to the engine's valves and internal moving parts. If the pump fails, the engine does not get adequate oil. The result could be a seized engine. The first sign of oil pump failure is the "check oil" indicator light. If you have a full oil pan, the likely cause for the light is a failing oil pump.
Remove the Toyota's oil pan drain plug with a wrench and drain the engine oil into a drain pan. Place the plug back into the oil pan and tighten it with the wrench.
Remove the bolts that hold the oil pan onto the bottom of the Toyota's engine block. The number of bolts depends on the size of the engine. However, the bolts are around the entire perimeter of the oil pan. Use a wrench to remove them.
Pull the pan off the engine block. Sometimes, the pan sticks due to the old gasket. If this happens, squeeze a metal scraper or a flat-blade screwdriver between the pan and the block and pry it free.
Clean the old gasket material off the bottom of the Toyota's engine block and mating surface of the oil pan with a metal wire brush, clean towels and white spirit.
Unplug the wiring harness from the oil pump.
Loosen the jam nut that secures the oil pump to the oil pickup tube with a wrench. Rotate the pump counterclockwise to remove it from the pickup tube. Thread the new oil pump onto the pickup tube and secure it with the jam nut and wrench.
Plug the wiring harness into the new oil pump.
Place the new gasket onto the mating surface of the oil pan. Place the oil pan against the engine block. Thread each bolt into the oil pan using your fingers and then tighten the bolts with the wrench.
Remove the oil filler cap located in the engine bay and drain 4 qts. of engine oil into the engine. Close the cap once finished.