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Missing vacuum lines

  • Thread starter Thread starter tuhockey11
  • Start date Start date Nov 27, 2007
T

tuhockey11

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Apr 7, 2003
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Nov 27, 2007
#1
  • Nov 27, 2007
  • #1
I have been trying to find the source of my high idle and it seems to be a vacuum issue. There is no vacuum line going to the EGR valve. I didnt see one anywhere around it that could have fallen off, etc. I seem to remember on previous Mustangs Ive owned that there is a black box of some sort that a few vacuum lines go into (including the EGR), but it is not there on this car. Does anyone have a diagram or picture that I can go off of to reproduce what is supposed to be there? Any suggestions?
 

cjones

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Nov 28, 2007
#2
  • Nov 28, 2007
  • #2
what year vehicle??
 
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Fox8950

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Jun 29, 2007
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Nov 28, 2007
#3
  • Nov 28, 2007
  • #3
Heres a link to a diagram of how the vac lines are supposed to be run. http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg

The little black box I think your talking about is just a plug with 4 lines running into either side. Your TAD & TAB solenoids,EGR vacuum regulator, and vacuum reservoir plug into one side and the lines running out go to the diverter & bypass valve , EGR valve, and manifold vacuum source (the diagram doesn't show the way my stuff is all hooked up as far as line routing but is a great reference for what goes where.
 
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tuhockey11

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#4
  • Nov 28, 2007
  • #4
Thanks for the diagram, car is a 92 GT. Do i need that plug or can i just route the lines directly?
 
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Fox8950

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#5
  • Nov 28, 2007
  • #5
I don't see any reason you couldn't route them directly it seems to serve as nothing more than an easy spot to disconnect (which is nice)

** Lol come to think of it I have 1 vacuum line in that whole mess I didnt cap off when I deleted my smog egr stuff and thats the one from the manifold vacuum source to the reservoir.
 
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tuhockey11

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#6
  • Nov 28, 2007
  • #6
Ill have to take a look at the car later when i get home. I didnt see any vacuum lines in tha area at all....The smog pump was deleted by the previous owner, I guess he just decided to take everything out. Hope I can figure it all out again
 
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tuhockey11

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#7
  • Nov 28, 2007
  • #7
Ok guys, I was able to take a good look at it after work today. I will start with what is correct; Manifold vacuum line to distribution block, brake booster, A/C system lines, cruise control line, FPR line, PCV line. Now for the problem areas. Fist problem noted was that the vacuum line coming out of the manifold to the front of the engine goes to the valve but then is just hanging off after that. It does not coonnect to the charcoal cannister, i dont even see it. Where is it supposed to be? Probably removed by previous owner. Next, there is no line going to the EGR valve, and there is what looks like a solenoid of some sorts on the rear pass side of the engine bay that has two vacuum ports, but no hoses (has wiring harnesses attached to it) Im assuming this is the EGR solenoid. Next, there is a little line coming from the back of the plenum that goes nowhere, looks like hose was removed. Also, going from the diagram posted above, there is no check valve anywhere, gues that whole section of hose was removed. Basically, everything on the pass side rear of the engine bay is gone. However, my HVAC controls all work fine, but there are no lines where is is supposed to be? Also, there seems to be no vacuum cannister. Lastly, where are the lines for the smog equipment? Diverter valves, etc? Sorry for the long post, but I am not too familiar with these cars yet. Im usually pretty good with this stuff, but the diagram doesnt seem to match up to the actual application to well. Is there a more relatable diagram anywhere, or would someone mind posting pictures of their actual engine showing these lines hooked up? Really want to get this situation worked out, because everything else on the car is excellent. Thanks in advance for any replies
 
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Fox8950

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Jun 29, 2007
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Nov 28, 2007
#8
  • Nov 28, 2007
  • #8
Mine doesn't have that check valve either, the vacuum reservoir is located up in the pass. side fender so you can't see it w/out pulling the fender liner out. Was the line coming out of the back of the plenum capped off or plugged? It sounds like someone just removed a huge hunk of stuff on ya. I'll get some pics posted up for ya tomorrow, like I said the diagram doesn't show the way my stuff is all hooked up as far as line routing but is a great reference for what goes where.
 
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tuhockey11

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#9
  • Nov 28, 2007
  • #9
That exactly what it looks like, I would appreicate it if you could post some pics, thanks
 
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