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Resolved Emissions Reserve vacuum routing in passenger side wheel well

  • Thread starter Thread starter Yyhoop
  • Start date Start date Nov 4, 2023
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    1991 mustang lx 5.0
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85GTStangGuy

5 Year Member
May 19, 2021
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Jax, Florida
Nov 6, 2023
#21
  • Nov 6, 2023
  • #21
Yyhoop said:
who has the better shop manual for 1991 stangs?
Click to expand...

One of the ebay ones?!....

1991 Ford Mustang Shop Service Repair Manual CD Engine Drivetrain Electrical OEM | eBay

Body, Chassis, Engine, Drivetrain & Electrical. Loaded with diagrams & illustrations to help disassemble, repair & reassemble various components. Searchable CD. Uses Adobe Acrobat Reader 7.0 and higher to view the manual.
www.ebay.com

1991 FORD / LINCOLN / MERCURY MASTER WIRING DIAGRAM SET / SHOP MANUAL MUSTANG++ | eBay

THIS BOOK IS AN ORIGINAL. IT IS A GOOD -- BUT NOT PERFECT -- MASTER WIRING DIAGRAM MANUAL.
www.ebay.com

NEW 1991 FORD MUSTANG ELECTRICAL VACUUM SERVICE SHOP EVTM MANUAL | eBay

This auction is for an Original Ford Electrical Vacuum Troubleshooting Manual - EVTM MANUAL. This is the factory Ford manual absolutely ideal for any owner with complete wiring and vacuum details for service, troubleshooting, diagnosis and more! This is a Factory Ford manual so you know of both...
www.ebay.com
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,264
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224
Massachusetts
Nov 6, 2023
#22
  • Nov 6, 2023
  • #22
I have the 1991 EVTM. I can take a pic of the relevant page.

Im confused on what exactly the question is. One vac reserve goes to the HVAC controls and the other is for the EGR/TAD/TAB
 
Last edited: Nov 6, 2023
Reactions: Yyhoop

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
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polk county florida
Nov 6, 2023
#23
  • Nov 6, 2023
  • #23
Mustang5L5 said:
I have the 1991 EVTM. I can take a pic of the relevant page.

Im confused on what exactly the question is. One vac reserve goes to the HVAC controls and the other is for the EGR/TAD/TAB
Click to expand...
His HVAC is connected, he apparently has two black vac lines that appear to be broke/cut off, only one nipple on the vac can.
 

85GTStangGuy

5 Year Member
May 19, 2021
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Jax, Florida
Nov 6, 2023
#24
  • Nov 6, 2023
  • #24
@Yyhoop - I think you should just tee those 2 lines together and connect them to that vacuum can with the open connector. Looking at the vacuum diagrams it doesn't look like there's a check valve near that hose junction. See what happens. Is the car actually running at present?
 
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Yyhoop

Member
Nov 4, 2023
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Vernon Florida
Nov 6, 2023
#25
  • Nov 6, 2023
  • #25
85GTStangGuy said:
@Yyhoop - I think you should just tee those 2 lines together and connect them to that vacuum can with the open connector. Looking at the vacuum diagrams it doesn't look like there's a check valve near that hose junction. See what happens. Is the car actually running at present?
Click to expand...
That's what I did. I teed them together and ran a single line to the vacuum can. I also replaced the EGR valve and position sensor. The car seems to be running great, much better than when none of that stuff was hooked up. I'm pretty sure the EGR valve was original. I still need to replace the EGR, TAB and TAD solenoids. I'm pretty sure its all original. It's responsive, shifts nice (automatic) and the RPM bounce is gone.

Still have a lot of cosmetic work to do on it but mechanically it seems good.

CJP and LMR seem to be fairly popular, do you have a preference for buying cosmetic type items. There is very little on the car cosmetics that doesn't need to be replaced. (Labor of Love)
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,264
17,952
224
Massachusetts
Nov 6, 2023
#26
  • Nov 6, 2023
  • #26
General karthief said:
His HVAC is connected, he apparently has two black vac lines that appear to be broke/cut off, only one nipple on the vac can.
Click to expand...

It appears he’s missing the HVAC ball completely. There are two vac cans.

One vac line to the small cylinder, and another vac line to the ball.
 

Yyhoop

Member
Nov 4, 2023
26
8
13
Vernon Florida
Nov 6, 2023
#27
  • Nov 6, 2023
  • #27
Mustang5L5 said:
It appears he’s missing the HVAC ball completely. There are two vac cans.

One vac line to the small cylinder, and another vac line to the ball.
Click to expand...
The HVAC ball is there and hooked up. I still had two additional vac lines that were chewed off (not the vapor return line to the fuel tank)in the wheel well. After further investigation and help here I ran them into a tee connector than a single line to the emissions can.

Car is running great.

Thanks everyone who helped me out with this.
 
Reactions: General karthief and 85GTStangGuy

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,951
10,589
203
polk county florida
Nov 6, 2023
#28
  • Nov 6, 2023
  • #28
And another satisfied customer,
 
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