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Here's the procedure on how to install/replace fuel pump for your Chevy malibu.
Raise the rear of the vehicle and place jack stands under the pinch welds on the lower body rocker panel. There are reinforced areas here that are designed to support the weight of the vehicle. Lower the car onto the jack stands and remove the floor jack. Unscrew the fuel filler cap to help relieve pressure that builds up in the tank due to fuel evaporation.
Disconnect the plastic fuel lines leading from the tank to the front of the vehicle by pushing in on the line while depressing the quick disconnect fittings. Unplug the vapor return line and the fuel pump's electrical connector. Remove the fuel filler neck hose by loosening the hose clamps with a screwdriver and prying the hose loose with a large pry bar.
Remove the two rubber exhaust system hangers located near the rear of the exhaust. This will allow the exhaust to move when removing the fuel tank. Remove the metal heat shield from the bottom of the car.
Place the floor jack under the fuel tank, with a large flat piece of wood between the jack and the tank, and lift the tank slightly. This will take the weight of the tank off the straps attaching the tank to the undercarriage of the car. Remove the straps holding the tank to the body of the car, and lower the fuel tank. Slide the fuel tank past the exhaust system, and out from underneath the car.
Remove the fuel pump assembly by turning the spring-loaded retaining ring with the hammer and chisel. Lift the whole assembly out of the fuel tank by lifting the assembly up and then rotating it over to clear the level sensor arm. Unsnap the top, and separate the plastic housing to gain access to the fuel pump. Remove the fuel pump electrical connector, and remove the pump from the assembly by pushing the pump up and over until it clears the assembly.
Install the new pump into the assembly using the new rubber coupler and the new vibration cushion supplied with the pump. Plug the electrical connector into the new pump, and snap the two halves of the plastic housing back together. Install the assembly back into the tank, and rotate the spring-loaded retainer using the hammer and chisel.
Reposition the tank under the car, and lift the tank into place with the floor jack. Install and tighten the retaining straps, heat shield and filler neck hose clamps. Reinstall the exhaust system hangers. Plug the electrical connector back into the assembly. Reconnect the fuel lines and vapor line.
Lower the vehicle off the jack stands and prime the fuel system by cycling the ignition key from off to run a few times. Start the engine and check for leaks
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