2007 Rendezvous - Apparently intermittent / no power to fuel pump

onge_87GN

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Looking for ideas (at a loss).... over the course of the last year, 2007 RDV, replaced rusted out fuel lines. Soon there after, replaced fuel pump. Ran fine without issue for several months, but then fuel pump would stop priming at ignition turn. Replaced fuel pump relay....ran fine, but then it seemed the relays were overheating...fuel pump would stop.

Ended up replacing under hood fuse box (relay was extremely loose and would not seat) and ran fine for the past 2 months. Today, engine shutdown while driving...changing relay did not work....apparently a complete loss of power to fuel pump. I connected a 9V battery to the harness and can hear the pump in the tank.

No diagnostic codes thrown this time.... previous codes were lean fuel bank 1 and relay short to ground

Any thoughts?
 
It sounds like the relay female contacts are corroded, or loose fittings once again due to high amp draw? Have you ever changed the fuel filter? What is the fuel pressure when you jump the fuel pump with 9-v?
 
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With the 9V (measuring 6.6V) connected at the FP harness (body block -female)....14psi @ fuel rail....
For S & G , inserted diagnostic relay terminal into fuse block pos and applied same 9V to term 86 & 87a....30psi @ fuel rail...

Now vehicle starts....multiple times w/o hesitation.....
Not about to take it for a test ride...diff subject make matters worse, steering pump whining...ugh..
 
oh....replaced fuel sock on pump hanger when that was dropped in new....don't know of any "in-line" fuel filter
 
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