My 2005 chevy malibu is not getting gas. not sure if it is the built in anti theft causing it or if it is the fuel pump. how can u tell the difference. (the security theft light goes on and off) and where is the fuel pump located? in the gas tank?

Hello pass.... The fuel pump is in the gas tank. The malibu does not have any fuel filters it only has a strainer on the fuel pump itself. You will have to drop the gas tank to get to the fuel pump.
The Malibu Classic (8th letter of VIN is "F") with the 2.2 Ecotech 4-cylinder engine has a fuel filter between the fuel tank and the rear axle. One end of the filter has a threaded connector and the other is a typical compression style. Regarding the antitheft system, if that is the problem I recommend that you contact an autoelectric repair shop and get them involved as they have the diagnostic tools and the wiring diagrams to get to the bottom of these complex devices. Joe