[xsbchevy]

the cat has a lot to do with it. if its backed up the rear o2 wont read properly. o2's have control over the lean/rich mix. if it says ok im getting to much fuel i need to trun back the mix and vice versa. the way the dealer mech explained it is the passenger side was fighting over fuel mixture and threw the pump for a loop. it didnt kill it totally but it screwed up the fuel pressure. when mine went bad i would top out at 50 then slowly drop to about 10. id kill it set for 5 min and do the same thing again. i was getting about 10-15 miles before it started doing it again