Loss of power

Have a 2001 Chev Malibu as i drive it loses power stays running then comes back and runs normal with no specified time, diagnostics unable to pin point problem feels like loss of electrical but also seams like loss of fuel. filter been replaced

Measure the fuel pressure with the engine under load. You can load the engine by putting the gear shift into DRIVE, and running the engine at 2,000 rpm for a couple of minuets. Another way is to attach the fuel pressure gauge, place the gauge where you can see it as you drive; then, drive and observe the fuel pressure.