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Vacuum routing question/issues

  • Thread starter Thread starter Vulpes5.0
  • Start date Start date Jan 4, 2019
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    foxbody vacuum

Vulpes5.0

5 Year Member
Nov 17, 2018
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Warner Robins, Georgia
Jan 4, 2019
#1
  • Jan 4, 2019
  • #1
I've got a 1987 Mustang 5.0, AOD transmission. Someone before me did a smog pump delete, I don't really think they did it properly but that's something for another day. I have two vacuum lines that I'm not quite sure where they belong. I'm assuming that one belongs on part of the smog system that's gone, but looking at vacuum diagrams is just a struggle for me, and Youtube videos aren't much help either. My car runs, but doesn't run well at all. It idles a little bit rough, and after a couple minutes will idle up to around 2000 RPM and begin going up even more from there. where do these vacuum lines belong, or should i plug them somehow? I'm not sure. My car still has the EGR system despite the smog pump's removal. any help is greatly appreciated. i put a picture of me holding each line, and a picture of where they enter the vacuum tree or whatever it's called.
 

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Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,164
17,860
224
Massachusetts
Jan 4, 2019
#2
  • Jan 4, 2019
  • #2
Top solenoid is egr vacuum regulator bottom two are for the tad/tab that was part of the smog system.

From the looks of it the bottom one is hooked to the egr which is incorrect. You are probably opening the egr at the wrong time causing it to stumble.

With the smog pump gone, you can just cap the two vsc lines off the bottom, but the white line you are holding in your hand goes to the egr. You can see how it almost lines up properly in the pic

Egr and air pump are two different systems. Air pump is needed with cats, so if they are gone you can remove the pump with no ill effect. Egr is different. Since yours is intact, I'd fix that vac line
 
Reactions: General karthief

Vulpes5.0

5 Year Member
Nov 17, 2018
143
27
38
Warner Robins, Georgia
Jan 4, 2019
#3
  • Jan 4, 2019
  • #3
Mustang5L5 said:
Top solenoid is egr vacuum regulator bottom two are for the tad/tab that was part of the smog system.

From the looks of it the bottom one is hooked to the egr which is incorrect. You are probably opening the egr at the wrong time causing it to stumble.

With the smog pump gone, you can just cap the two vsc lines off the bottom, but the white line you are holding in your hand goes to the egr. You can see how it almost lines up properly in the pic

Egr and air pump are two different systems. Air pump is needed with cats, so if they are gone you can remove the pump with no ill effect. Egr is different. Since yours is intact, I'd fix that vac line
Click to expand...
is there any chance I could see any good pictures of how things look down in the passenger side corner and running along the firewall?
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,164
17,860
224
Massachusetts
Jan 5, 2019
#4
  • Jan 5, 2019
  • #4
I don't have any but I'll see if I can take some later or find one on Internet
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,164
17,860
224
Massachusetts
Jan 5, 2019
#5
  • Jan 5, 2019
  • #5
Some pics I got off the net. The TAB/TAD are the bottom two solenoids and EGR is on top


If you had the smog pump, this is where two lines from the TAD/TAB would go


And some details of the egr lines. Black is the source to the regulator and white is the return to egr

 

Vulpes5.0

5 Year Member
Nov 17, 2018
143
27
38
Warner Robins, Georgia
Jan 5, 2019
#6
  • Jan 5, 2019
  • #6
Mustang5L5 said:
I don't have any but I'll see if I can take some later or find one on Internet
Click to expand...
If you can’t, don’t worry, i just want some good reference pictures of what’s right. I look it up online and i often see those 5 lines going into one solenoid on older cars i believe, the solenoid that’s kind of reminiscent of a cylinder with 4 on one end and 1 on the other
 
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