What could cause the fuel pressure to "bleed off" when the Jeep sits for awhile?
Fuel pressure regulator?
Is there some sort of one way valve between fuel pump and fuel rail??
To get it running, I've been "jumping" the connection on the fuel relay to activate the pump manually for a sec ... then it primes up to 30psi and stays that way.
And the next day or so -- its back to 0 psi, even when I turn on the Jeep for the first time. But kicking off the pump for a sec primes it and then it seems to stay working for awhile.
1992 Jeep Cherokee Laredo
4.0L 6 cyl - fully rebuilt 2006
new fuel pump 6 months and then 3 weeks ago