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first time using vacuum gauge

  • Thread starter Thread starter legalize420
  • Start date Start date Aug 13, 2005

legalize420

Active Member
May 21, 2005
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37
South Florida
Aug 13, 2005
#1
  • Aug 13, 2005
  • #1
i just picked up a vac/fuel gauge and i have a few questions. where is the best place to connect it to? also, what is a good reading on the gauge? thanks
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
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Aug 13, 2005
#2
  • Aug 13, 2005
  • #2
The vac tree works for me. Look for 15-20 in-hg.
Good luck.
 

legalize420

Active Member
May 21, 2005
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Aug 13, 2005
#3
  • Aug 13, 2005
  • #3
what about the fuel. where do you connect that and what reading?
 

HoofnIt

Founding Member
Jan 8, 2001
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North Carolina
Aug 13, 2005
#4
  • Aug 13, 2005
  • #4
The fuel pressure can be checked at the schrader valve on the front part of the passenger side fuel rail. Just remove the cap to gain access.
 

legalize420

Active Member
May 21, 2005
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37
South Florida
Aug 13, 2005
#5
  • Aug 13, 2005
  • #5
whats a good reading on the gauge
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Aug 13, 2005
#6
  • Aug 13, 2005
  • #6
For FP, at simulated WOT (vac line off and capped), 38-39 PSI is stock.

With the vac line hooked up (as it is when you drive the car), 30+ PSI is within spec.

Good luck.
 

legalize420

Active Member
May 21, 2005
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South Florida
Aug 13, 2005
#7
  • Aug 13, 2005
  • #7
HISSIN50 said:
For FP, at simulated WOT (vac line off and capped), 38-39 PSI is stock.

With the vac line hooked up (as it is when you drive the car), 30+ PSI is within spec.

Good luck.
Click to expand...

if i use the schrader valve as mentioned above, which one would that be. you lost me on this.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Aug 13, 2005
#8
  • Aug 13, 2005
  • #8
legalize420gt95 said:
if i use the schrader valve as mentioned above, which one would that be. you lost me on this.
Click to expand...
Cool, that is what I was trying to do.




J/K. Hook your gauge up to the Schrader valve (looks like a tire's valve). Start car, check for leaks. If safe, Note the pressure with the car idling. It should be 30-34 PSI.

Now remove the vac line on the FPR, and cap the line with your finger (cap the rubber line, not the hard fitting on the FPR). The pressure should shoot up to 38 PSI+. This latter reading is a simulation of WOT (at WOT, there is very little manifold vac, and by removing the vac line, you simulate that condition as far as the FPR is concerned).

Cool? If not, post and I or someone more articulate can help.
 
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