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car runs lean...

  • Thread starter Thread starter 90mustangfan
  • Start date Start date Oct 19, 2005

90mustangfan

New Member
Oct 18, 2005
93
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0
So cal
Oct 19, 2005
#1
  • Oct 19, 2005
  • #1
how can I test the stock fuel pressure regulator to see if its bad or not?
 
E

emagdnim

Active Member
Feb 5, 2003
391
15
28
Oct 19, 2005
#2
  • Oct 19, 2005
  • #2
90mustangfan said:
how can I test the stock fuel pressure regulator to see if its bad or not?
Click to expand...

Hook up a fuel pressure guage and see what your pressure is.
 

notchback

Founding Member
May 30, 2000
1,950
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St Clair Shores MI
Oct 19, 2005
#3
  • Oct 19, 2005
  • #3
yup like he said...i would run it hard too , to see if drops or anything...you can tap into the schrader valve and just hold the guage outside the window if you don't wanna mount it...there cheap ones you canmount right on the rail, but obviosly you can't see it driving
 

dilligaf

New Member
Nov 24, 2004
25
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Midwest city, ok.
Oct 20, 2005
#4
  • Oct 20, 2005
  • #4
would a bad fuel regulator make my car idle up and down?
I have a pressure gauge but the pressure is never the same. One minute it will be at 35, the next 30, then 38. And sometimes the pressure will change when i take the vac. line off, sometimes it won't. Sometimes it will change by 2# other times 4#. I'm pretty sure its bad, but my car has this idle problem and was wondering what the odds are that a new regulator might help.
 

jrichker

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Mar 10, 2000
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Dublin GA
Oct 21, 2005
#5
  • Oct 21, 2005
  • #5
See the sticky "Help me create the Surging Idle Checklist" at the top of the forum for help with your idle problems.
 

Zero_chance

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May 29, 2001
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Maricopa, AZ
Oct 21, 2005
#6
  • Oct 21, 2005
  • #6
I would run the checklist before you start getting eager t oswap out parts. The pressure should change when you disconnect the vac line.
 
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