Power but no fuel pressure after 3 new pumps
I have lurked on and off on this site since I bought my Ranger in 2000 and it has saved me and my wallet many times. My favorite was a repair to the door lock actuator using aluminum foil which is still going strong 5 years later. I have searched about my latest problem (no start with p0171 & p0174), but I haven't found a post that covers my issue.
6 weeks ago my truck died in my (uphill inclined) driveway. I went outside, started it up to let the a/c run, then went back out 5 mins later just in time to see it idle really badly and die on me. No CEL, just dead truck (cranked, but didn't start). It's my only transportation at the moment, so I thought I'd just have it towed and fixed instead of figuring it out over a few days myself.
The mechanic replaced the fuel pump, it ran for a few days, then CEL came on, then it died a couple of days later. Towed back to mechanic, it started up fine and I drove it home. Next day CEL again then it died a couple of days later. Towed back and mechanic changed the pump 2nd time. A few days later and the same thing. CEL, then it died in a few days. Checked codes (the mechanic hadn't) and got P0171 & P0174. Checked fuel pressure at the schrader valve (10psi) and replaced the filter and pump. Truck started for a few seconds and died. Still @10psi. I have a sense of achievement having dropped the tank and replaced the pump, but my sense of achievement won't get me to work. Each time I can feel when it's about to go (rougher idle, couple of cranks to start, etc)
I can hear the pump and the relay no problem. Could this be electrical? Where do I check power to the pump? Could the fuel line be blocked on the engine side of the filter? The tank was pretty clean and the fuel lines on the tank side were OK (until I put a kink in one - another $20).
2000 Ranger 3.0 flex manual trans w/127k
What do I need to replace (apart form the mechanic)?