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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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fuel pressure vacuum

  • Thread starter Thread starter 1991vert
  • Start date Start date Apr 12, 2005

1991vert

10 Year Member
Feb 27, 2004
1,103
7
69
Ludlow, MA
Apr 12, 2005
#1
  • Apr 12, 2005
  • #1
everytime i set my FP to 40 with the vacuum off it somehow always gets messed up. am i supposed to run the car with the vacuum off?? or just set the FP with the vacuum off then put the vacuum line back on?
 

whitehorseupnorth

SSoM President
Founding Member
Sep 9, 2000
1,772
0
36
Maine
Apr 12, 2005
#2
  • Apr 12, 2005
  • #2
You need to pull the vac line off to set your FP. With the vac line off it will simulate WOT. Cause, at WOT there is no vaccum. Now, after setting the FP and then connecting the vac line, the FP will go down cause the vaccum from the engine will act against the spring inside the FPR. Pull vac line, set FP, reconnect vac line. Pretty simple..
 

1991vert

10 Year Member
Feb 27, 2004
1,103
7
69
Ludlow, MA
Apr 12, 2005
#3
  • Apr 12, 2005
  • #3
ya but then i'll check it again the next day with the vac off and it will read like
35 psi.
 

1991vert

10 Year Member
Feb 27, 2004
1,103
7
69
Ludlow, MA
Apr 12, 2005
#4
  • Apr 12, 2005
  • #4
also should i do this when the car is hot? or at initial start up (cold)?
 
1

1990LXDropTop

New Member
Dec 4, 2003
430
0
0
Western Massachusetts
Apr 12, 2005
#5
  • Apr 12, 2005
  • #5
1991vert said:
also should i do this when the car is hot? or at initial start up (cold)?
Click to expand...

It is best to set it when the car is fully warmed up at normal operating temp.
 
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