To change an oil pump, raise the car, and secure it. Drain the oil into an approved container, and remove the oil pan. Locate the oil pump, which is typically on the back of the motor and connected to a filter, and disconnect the pickup tube. Remove the bolts holding the pump in place to release it. Set the new oil pump into place, secure it with the bolts, connect the filter and pickup tube, and replace the oil pan.
To drain the oil, set the drain pan under the oil pan, and remove the plug on the bottom of the oil pan with a socket. Remove the bolts on the sides of the oil pan to release it. If the oil pump isn't visible after removing the oil pan, refer to the owner's manual to determine the location of the pump.
Before replacing the oil pan, scrape the old gasket off the oil pan, and install a new gasket. Allow the gasket material to harden for 30 minutes before reinstalling the oil pan. Replace the oil pan plug, and lower the vehicle. Add the recommended amount and type of oil according to the owner's manual.
With the engine started, visually examine the engine for oil leaks. Check the oil pressure gauge to ensure the repair is successful.