Fuel pressure 30,40 20 psi???

Discussion in '94-95 5.0 - Specific' started by 101vet, Jan 10, 2014.

  1. 101vet

    101vet Active Member

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    So tomorrow hopefully if the UPS man comes a knocking i can install my Dizzy and new ICM, Until then i fiddle with things...

    So i have a question about fuel PSI, When i key the ignition it comes to 40PSI 3-5 secs, then drops to 30PSi once started, raise the throttle (quick snap of the go stick ) it jumps to 35psi, No surging and holds 30psi while at idle. reason i ask is i've been tracking down my crank no start, and noticed that if i crank it and it doesnt start and key the ignition 2-3 times it'll start, So i did the Fuel PSI test.

    Is this with in spec? I tried looking but my phone isn't being nice today.... 95 5.0ltr car in question. Also if anyone is in Phoenix and would want to lend their knowledge or a hand i'll supply beer and witty banter
     
  2. RichV

    RichV Well-Known Member

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    Yes, that is fine. If you pull the vac line off the regulator it will be at around 40 which is normal. Under vacuum it will be less.
     
  3. 101vet

    101vet Active Member

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    You are correct sir...Thanks for the response.... Ill move back to the ignition side of things for now

    Sent while in your Mom
     
  4. Paul

    Paul Well-Known Member

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    SPec is 39 psi with the vacuum unhooked.
     
  5. 101vet

    101vet Active Member

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    Okey so did the test again today....

    Primed to 37psi, started it and was running at 34psi, psi didnt change whether the vac hose was connected or not... Car was completly cold when i did it this time .

    First test was after driving home in traffic car was up to temp...

    Sent while in your Mom
     
  6. 101vet

    101vet Active Member

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    Fuel PSI reg going bad?

    Sent while in your Mom
     
  7. Addermk2

    Addermk2 Well-Known Member

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    FPR might not be the issue. Your pump might not be putting out enough.
     
  8. CC'S95GT

    CC'S95GT Well-Known Member

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    How old is the fuel filter?
     
  9. 101vet

    101vet Active Member

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    Filter is brand new...I left the gauge connected overnight, gonna see what it does when i key it on, In my mind it should give me 40psi during the 3 sec run time prior to start up...

    Sent while in your Mom
     
  10. 95opal

    95opal Well-Known Member

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    im with addermk sounds like the pump might be on its way out.
     
  11. 101vet

    101vet Active Member

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    I agree... Gonna grab one and replace it...

    Sent while in your Mom
     
  12. 95opal

    95opal Well-Known Member

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    For the couple of extra bucks over a stock pump I would grab a 255lph pump and be done. This way youll be set for any future mods.
     
  13. 101vet

    101vet Active Member

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    I was looking at the BBK kit on american muscle.... Has good reviews and a direct replacement...

    Sent while in your Mom
     
  14. toyman

    toyman Well-Known Member

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    You want a Walbro GSS340 pump.
     
  15. 101vet

    101vet Active Member

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    Why not the 255? I dont have plans on any big power numbers out of the car... Heads,cam,intake,exhaust about it for the motor....

    Sent while in your Mom
     
  16. RichV

    RichV Well-Known Member

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    GSS340 is a part #. It is a 255lph.