Engine Need Help With Vacuum Lines

2cars10

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Nov 12, 2020
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I believe these are AC lines but can someone confirm this? If it's not ac what are these for? I'm asking because the hose connected to the canister is pretty dry rotted
vacuum1.jpg
vacuum2.jpg
vacuum3.jpg
vacuum4.jpg
 
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KRUISR

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I have a Fox, but believe these are similar. Pic 1 I believe is part of emissions system. On a Fox the vacuum for HVAC is a small diameter line with a check valve and splitter located in the area of your pinky in the first pic. The two lines go the vacuum reservoir in passenger fender and the other through the firewall to HVAC unit. I believe that is all the vacuum HVAC gets.

The lines in pics 3 and 4... where do they come from/go to? They are about the size of the HVAC line to check valve on a Fox.
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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First two pics are the purge canister solenoid, it vents the fuel tank and works for part throttle cruise, fix the hose.
The other is likely the hvac vacuum hose.
Verhuseful.com may help with vacuum routing
 
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2cars10

New Member
Nov 12, 2020
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Virginia
First two pics are the purge canister solenoid, it vents the fuel tank and works for part throttle cruise, fix the hose.
The other is likely the hvac vacuum hose.
Verhuseful.com may help with vacuum routing
That website isn't working for me do you have an alternative?
 

2cars10

New Member
Nov 12, 2020
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0
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Virginia
I have a Fox, but believe these are similar. Pic 1 I believe is part of emissions system. On a Fox the vacuum for HVAC is a small diameter line with a check valve and splitter located in the area of your pinky in the first pic. The two lines go the vacuum reservoir in passenger fender and the other through the firewall to HVAC unit. I believe that is all the vacuum HVAC gets.

The lines in pics 3 and 4... where do they come from/go to? They are about the size of the HVAC line to check valve on a Fox.
The Very small lines came from a box on the driver side that said AC if i remember correctly, I found that after I posted this though
 

Chythar

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Aug 26, 2004
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The very small line feeds vaccuum to the HVAC system in the car. With that line unhooked, air will only blow through the defrost vents (the ones by the windshield). The line goes from a vaccuum distribution block on the driver's fender to a hole in the firewall on the passenger side.
 

mostsmooth

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2cars10, that first pic, do you know the size and length of that hose in your left hand?
thanks

Edit: i think its 1/4", but mine is in such bad shape i want to be sure
 
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mostsmooth

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First two pics are the purge canister solenoid, it vents the fuel tank and works for part throttle cruise, fix the hose.
The other is likely the hvac vacuum hose.
Verhuseful.com may help with vacuum routing
between the purge canister and the fuel tank is the charcoal canister, is that correct? and the charcoal canister is in the fender? do i have that all correct?
thanks
 

KRUISR

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Charcoal canister is the purge canister, it is the box mounted to passenger front frame rail up by the rad. Line going into canister comes from fuel filler tube (i believe).

Plastic "tank" in passenger fender well is a vacuum reservoir to store extra vacuum for HVAC system. It connects downstream of the check valve on the firewall. The small line in the OP's pics go to the check valve.
 

mostsmooth

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Charcoal canister is the purge canister, it is the box mounted to passenger front frame rail up by the rad. Line going into canister comes from fuel filler tube (i believe).

Plastic "tank" in passenger fender well is a vacuum reservoir to store extra vacuum for HVAC system. It connects downstream of the check valve on the firewall. The small line in the OP's pics go to the check valve.
im looking at a diagram on veryuseful.com and it shows it configured as i described, thats weird. maybe the diagram is for a differnt year than my 95
 

mostsmooth

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Maybe we are getting terminology wrong. The charcoal canister is the rectangular box. Could the purge canister really be the purge solenoid (or purge valve) which is the small cylinder connected at the charcoal canister that opens and closes vapor flow to the intake.


In this diagram they are along the bottom towards the right.
thats the diagram i was looking at, and those are the thing i am talking about., and now im thinking its not for a 95. i cant find something that specifically says 95 on it.
the purge canister is what i thought was on the firewall that the OP is holding in pic 1. the charcoal canister i was guessing was in the fender, but i could be way off. i followed the hose to the left coner passenger side and it disappeared to a point i couldnt trace it anymore.
 

KRUISR

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The diagram I linked to is for an '88. My car is a '90.

IMG_0245.JPG

Charcoal canister is located bottom mid of this pic, just 4" or so behind the rad support.

IMG_0672.JPG

In the bottom left, find the charcoal canister and you can just see the top of the purge valve just behind the canister. The discharge from the purge valve tucks under the alternator bracket and up to the vacuum port on the front of the intake (mid of the pic).

I looked at your other pics and yes, you are holding the purge valve at the firewall (above the A/C evaporator). I am not familiar with the factory installed location of this valve on a '95, my pics are on a '90, so some differences are possible.
 
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General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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94-5 purge canister is behind the right front wheel, you have to pull the inner fender liner to see it. That's why the purge valve is in the back corner of the firewall.
 

mostsmooth

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thanks
just so i
94-5 purge canister is behind the right front wheel, you have to pull the inner fender liner to see it. That's why the purge valve is in the back corner of the firewall.
just so i have the terminology correct and have an idea of whats what:
the purge valve is what is being held up in pic 1 in the original post, the purge canister is in the fender, and there is no charcoal filter on 94-95 gt?
thanks
 
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General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
18,825
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polk county florida
Dude, stop adding things,
Vacuum line from the intake to the purge valve, line from valve to canister, the canister contains charcoal, vacuum line back to tank.
During part throttle cruise the computer opens the valve and pulls fumes from the fuel tank through the canister into the intake to fatten up part throttle cruise and keeps the canister from filling up with fuel.
That is my understanding anyway.
 

mostsmooth

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Dude, stop adding things,
Vacuum line from the intake to the purge valve, line from valve to canister, the canister contains charcoal, vacuum line back to tank.
During part throttle cruise the computer opens the valve and pulls fumes from the fuel tank through the canister into the intake to fatten up part throttle cruise and keeps the canister from filling up with fuel.
That is my understanding anyway.
ok thanks. obv i wasnt aware the purge canister was the same thing as the charcoal canister.