I have a 02 3100 malibu pumping 7 lbs, the problem the car will start every time for 4 or 5 weeks straight, then one day it will not start, at first i though it was the security system , had it to the dealer a few times, they changed the iginition switch, other than that they couldn't find anything, didnt have any codes, the bigger problen till i got it hauled to the dealer and they looked at it the car started. still done the same thing, finally discovered that there was no fuel pressure with the key on motor stopped, figured it was the check valve at the pump, i was tolded, had a new factory pump installed, worked good for about 2 weeks, then one evening it would not start, happened twice in 30 minutes, each time i managed to get it started, it was flooded , could smell raw gas, smoked out the tail pipe bad , missed and idled bad till it got cleaned out, though it was the fuel regulator, i changed it, now it starts every time, fuel trims are good, but pressure at idle is about 10 lb low, car runs pretty good , but i'm down about 3 mile per gal, the problen i have NO fuel pressure with the key on, engine off. pressure checked at fuel rail.