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'91 Pathfinder fuel system issues

fastpakr

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Found some info in the factory documentation...

It's definitely supposed to give a 5 second priming pulse. But I haven't found anything about how long the system should maintain fuel pressure after shutdown (or after the priming pulse).
 

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fastpakr

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I got a moment to look at his truck today at lunch. Still wasn't able to stick a gauge on it again, but a couple of things stood out...
1) Clamping off the fuel return hose from the regulator seemed to speed up restarts a good bit. I think it's bleeding fuel pressure across the regulator back to the return line.

2) I'm seeing 12v on -two- terminals at the relay connector any time the key is on, and three of the four terminals also show very low resistance to ground. More testing required, but it definitely wasn't the results I was expecting.
 

dvdswan

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Bad FPR or vacuum to the FPR. The relay is probably toast too.
 

fastpakr

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V8 Engine Swap
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113
Location
Roanoke, VA
Vehicle Year
1999
Make / Model
Ford
Engine Type
V8
Engine Size
5.0
Transmission
Automatic
2WD / 4WD
4WD
Tire Size
285/75-16
Those tests were of the relay socket with the relay unplugged.
 

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