If the fuel pump in your 2003 Chevy Malibu is not working properly, your fuel lines may not be pressurized enough, causing your engine to stall while you're driving or to have difficulty starting in the first place. Replacing a fuel pump in the Malibu is not the simplest job. The fuel pump resides in the fuel tank, and there's no access panel through the trunk, as there are in some other vehicles, to quickly get to it. Despite this irritation, the process is rather straightforward, albeit tedious. Expect to spend an entire afternoon on the project.
Prop open the hood of your Malibu. Disconnect the negative battery cable by loosening the negative battery terminal nut with your wrench. Set the cable aside.
Locate the Shraeder fuel pressure valve on the fuel rail near the injectors of the engine compartment. Place a rag over the valve. Press down on it to release the pressure of the fuel system.
Engage the parking brake. Raise the Malibu with your car jack. Lower the Malibu onto two jack stands.
Slide under the vehicle. Put on your latex gloves. Loosen the screw securing the metal hose rings around the vent and fuel hoses of the gas tank. Pull the collars away from the overlapping joint of the hose and fuel tank nozzles.
Place a drainage bin below the fuel hose. Get the syphon ready. Pull off the fuel hose from the gas tank. Quickly insert the siphon into the opening. Siphon out all of the gas from the tank into a gas can. This action is necessary because on the Malibu, the gas filler pipe, through which you could normally siphon out the gas from the tank, has a siphon block on it. Removing the gas makes it easier and safer to lower the tank.
Slide the floor jack under the gas tank. Remove one of the two straps holding up the gas tank. Allow one end of the gas tank to fall onto the floor jack. Pry the end away from the frame rail if it is stuck.
Reach over the gas tank. Disconnect the EVAP tube, the wiring harness and the return fuel line from the top of the fuel pump. Remove the other strap holding up the gas tank. Let the tank rest on the floor jack. Lower the floor jack enough to slide the gas tank out from under the Malibu.
Hit the metal tabs of the locking ring securing the fuel pump to the gas tank with your mallet and chisel. Hit the tabs in a counterclockwise direction until the tabs unseat from the gas tank slots. Pull off the locking ring. Pull the fuel pump out of the gas tank. Pull out the rubber o-ring from the opening.
Lubricate the new o-ring from the new fuel pump package. Set the o-ring on the opening of the fuel tank. Insert the new fuel pump into the gas tank. Seat the locking ring around the new fuel pump and into the slots of the gas tank.
Follow Steps 3 to 7 in reverse order to remount the gas tank.
Turn on the Malibu. Wait 10 seconds. Turn the Malibu off. Repeat this process 7 or 8 times until the engine turns over. This action pressurizes the fuel system.
