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Installed fuel pressure gauge...what should it read?

  • Thread starter Thread starter 91LX_5L
  • Start date Start date Aug 25, 2005

91LX_5L

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May 13, 2002
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Aug 25, 2005
#1
  • Aug 25, 2005
  • #1
I installed a rail mount fuel pressure gauge. It reads 32 when motor is running. Is that normal? What else should I look/test for, once its warmed up? with just igniton on etc? what are some numbers that are good so I know if somthing is wrong.
 

CManT1914

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Feb 5, 2004
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Killeen, Texas
Aug 25, 2005
#2
  • Aug 25, 2005
  • #2
It should read right around 30 at idle, and 39-40 under throttle or with the vacuum taken off the fuel pressure regulator.
 

91LX_5L

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May 13, 2002
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Aug 25, 2005
#3
  • Aug 25, 2005
  • #3
which vaccume is this? I dont have an aftermarket regulator. can you explain so i can find it, will it squirt out fuel? do i test at idle.

thanks man
 

CManT1914

New Member
Feb 5, 2004
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Killeen, Texas
Aug 25, 2005
#4
  • Aug 25, 2005
  • #4
91LX_5L said:
which vaccume is this? I dont have an aftermarket regulator. can you explain so i can find it, will it squirt out fuel? do i test at idle.

thanks man
Click to expand...


Honestly, if you're reading 30 or so at idle, and 39-40 when you hit the throttle, you're good to go.

But.... the vacuum line runs from the fuel pressure regulator to the intake manifold, on a vacuum tree on the elbow. It's small, and easier to take off the elbow than the actual fuel pressure regulator (for me anyway). If you take that vacuum line off, it's like you're under throttle, and so the fuel pressure goes up.

You'll need to remove that vacuum line if you ever get an adjustable fuel pressure regulator, and you try to set the fuel pressure.
 

91LX_5L

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#5
  • Aug 25, 2005
  • #5
ok the 39-40ish when on throttle is that like 1/2 throttle at what like 4,000rpm?

thanks
 

CManT1914

New Member
Feb 5, 2004
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Killeen, Texas
Aug 25, 2005
#6
  • Aug 25, 2005
  • #6
91LX_5L said:
ok the 39-40ish when on throttle is that like 1/2 throttle at what like 4,000rpm?

thanks
Click to expand...

Pretty much at any rpm. Now 1/3 throttle you should only see 34 or 35 or so. 2/3 throttle it should be up there. It's not really a set number for a set rpm and set throttle. As long as it climbs when you give it more throttle, then you're okay.
 

91LX_5L

Founding Member
May 13, 2002
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#7
  • Aug 25, 2005
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thank you
 

CManT1914

New Member
Feb 5, 2004
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0
Killeen, Texas
Aug 25, 2005
#8
  • Aug 25, 2005
  • #8
91LX_5L said:
thank you
Click to expand...

Anytime.
 
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