1986 f150 v8 5.0 Lariat XLT (Back tank deleted)

Hey everybody im clueless once again,

Been doing lots of repairs and maintanence checks everywhere to get it street ready, and a lingering issue since i bought the truck is fuel pressure.
At first fuel pressure was fine but would bleed within a minute, so went through and did the lines again and finally stopped the bleeding. Recently truck has been starting very very slow (like 10 psi eventually getting to 30 while cranking)
and finally i went through and checked the pressure again and it was rough. With about 6 primes it can get to the fuel pressure needed, and when i crank the pressure builds up to about 40 to run. I have replaced and tested
the intank pump and its problems, injectors have been replaced and recently replaced fuel filter. The high pressure pump runs, havent tested if it "really works" but it does run and moves gas. Back tank is deleted so the line of fuel goes
Tank- low pressure- high pressure- fuel filter- fuel rail- fpr- tank
There is a smell of gas out of the fpr, but i really dont think that is a reason since the rail isnt loosing pressure, even though the fpr isnt probably at its best. Might of missed some info so feel free to ask,

Hope someone can help,
Andrew

 

Yes, the FPR is a major problem. If there's gas in its vacuum line, replace the FPR.

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