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fuel pump promblem?

  • Thread starter Thread starter wshI_hd_1
  • Start date Start date Oct 31, 2004
W

wshI_hd_1

Founding Member
May 23, 2002
94
0
0
paulding, ga.
Oct 31, 2004
#1
  • Oct 31, 2004
  • #1
Ok, heres the promblem...at idle and normal driving condition my fuel pressure is 40# but once i hit WOT the fuel pressure shoots down to 20#. Is this the fuel pump or can it be the FPR (billet adjustable).I have no idea what size pump i have but what size should i run with the mods in my sig? (also, i have 24# injectors if it helps)...
thanks in advance.
 

Stang8URMPRT

Active Member
Dec 28, 2003
1,100
1
38
Daytona Beach, FL
Oct 31, 2004
#2
  • Oct 31, 2004
  • #2
Yes, it could possibly be your fuel pump. They are 90lph stock, which is good for about 300 hp. You look to be well over that with your parts. Go with a 190 or 255 and a new fuel filter. What seems to be happening when you go WOT and the fuel demand increases, your fuel pump cannot keep up with the demand, thus dropping pressure.

Nick
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Oct 31, 2004
#3
  • Oct 31, 2004
  • #3
but if the FPR is on the outs, you can have a 100 GPH pump running and the pressure will not be to spec (the FPR is returning too much fuel).

one can carefully crimp the return line to try to determine if the pump or FPR is at fault.

good luck.
 
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