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Fox No Smog... What Vacuum Lines Do I Need?

  • Thread starter Thread starter polaraman
  • Start date Start date Apr 20, 2016

polaraman

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#1
  • Apr 20, 2016
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I bought my 89 GT last year and it's bone stock with the exception of headers, flowmasters, and the smog has been removed. However, the canister and associated vacuum lines are still there. Do they still need to be there or can those vacuum lines and canister be removed? Could the lines be capped?
 

FoxMustangLvr

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#2
  • Apr 20, 2016
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polaraman said:
I bought my 89 GT last year and it's bone stock with the exception of headers, flowmasters, and the smog has been removed. However, the canister and associated vacuum lines are still there. Do they still need to be there or can those vacuum lines and canister be removed? Could the lines be capped?
Click to expand...
By canister do you mean the charcoal canister and purge solenoid? That helps vent the gas tank fumes and directs the fumes back into your engine. Removing this canister risks your garage smelling like gas a bit. I have had a couple 5.0's with them removed and didn't notice a smell but some people have had the smell. Up to you.

As far as all emission being removed, does this include your EGR as well? Can you post a pic of where your intake pipe connects to your throttle body and the vacuum lines in question?
 
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mikestang63

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leave the cannister on. It robs no HP and if you park your car in a garage without it, chances are your garage will reek of gas. You can always relocate it if you want to hide it in the inner fender.

Look for a vacuum line from the cannister solenoid on the passenger frame rail going to the upper intake and another hose from the solenoid going back to the gas tank
 

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When you say the canister and associated vacuum lines are still there are you talking about the 1/2 soup can canister in the passenger side fender above the tire?
 

mikestang63

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the black charcoal cannister that would be mounted on the inside of the passenger frame rail which jrichker pointed out in an earlier post
 

polaraman

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#6
  • Apr 21, 2016
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That was the canister I was referencing. I thought it was directly related to the smog and emissions stuff that's no longer there. It's not hurting anything but I was thinking it was causing my weird cold idle issues. I'll have to finish working through jrichkers's surging idle checklist i suppose.
 
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polaraman said:
That was the canister I was referencing. I thought it was directly related to the smog and emissions stuff that's no longer there. It's not hurting anything but I was thinking it was causing my weird cold idle issues. I'll have to finish working through jrichkers's surging idle checklist i suppose.
Click to expand...

So where are you routing the explosive exhaust fumes?


The problem with eliminating smog components is that is usually creates headaches for the user down the road when something doesn't run correctly. The truth is, the smog system robs the car of 0 HP, and most of the stuff is relatively harmless to leave intact and functional. For instance, removing the EGR system? What purpose does that serve? You gain 0 HP, lose a little crusing fuel economy, and end up chasing code 33's and 34's forever.

These cars are 30+ years old. Nissan Altima's off the dealership floor could take a Fox Mustang. Put your time and effort in making the car reliable and running in top shape. Most often, this involves keeping the smog stuff intact. It's just not worth it to eliminate it on stock, daily driven type cars.
 
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Mustang5L5 said:
So where are you routing the explosive exhaust fumes?


The problem with eliminating smog components is that is usually creates headaches for the user down the road when something doesn't run correctly. The truth is, the smog system robs the car of 0 HP, and most of the stuff is relatively harmless to leave intact and functional. For instance, removing the EGR system? What purpose does that serve? You gain 0 HP, lose a little crusing fuel economy, and end up chasing code 33's and 34's forever.

These cars are 30+ years old. Nissan Altima's off the dealership floor could take a Fox Mustang. Put your time and effort in making the car reliable and running in top shape. Most often, this involves keeping the smog stuff intact. It's just not worth it to eliminate it on stock, daily driven type cars.
Click to expand...
In this OP's case, I believe the emission components were removed by the previous owner and he bought it this way and he's trying to figure out what is what.
 

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FoxMustangLvr said:
In this OP's case, I believe the emission components were removed by the previous owner and he bought it this way and he's trying to figure out what is what.
Click to expand...

I read too fast sometimes....


Ok, in that case OP, don't rule out that the easiest solution may in fact be to put such said smog component back on.
 

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Mustang5L5 said:
I read too fast sometimes....


Ok, in that case OP, don't rule out that the easiest solution may in fact be to put such said smog component back on.
Click to expand...
Agreed and he should be able to get any emissions parts dirt cheap either from online forums or the local Pulln'save. Heck, I have a stock EGR with spacer sitting on my shelf just going to waste...
 

polaraman

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#11
  • Apr 22, 2016
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yes, you guys are spot on. I still have that canister on the car but i'm still experience some fumes so I'm thinking something still isn't hooked up right or has failed. I'll take a picture of what I have today or tomorrow. I hope you guys can point me in the right direction.
 

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polaraman said:
yes, you guys are spot on. I still have that canister on the car but i'm still experience some fumes so I'm thinking something still isn't hooked up right or has failed. I'll take a picture of what I have today or tomorrow. I hope you guys can point me in the right direction.
Click to expand...


The canister is pretty easy. One vacuum line runs to the front of the intake manifold and hooks up there. The other one runs to a vac line running to the gas tank. The wiring hooks up on the front pass side of the injector harness.
 

polaraman

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#13
  • Apr 29, 2016
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If everything is hooked up correctly, what could fail? Is there a way to troubleshoot the canister to make sure it's doing what its supposed to do?
 

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  • Apr 29, 2016
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Is the sensor on top plugged in?
 

polaraman

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where the electrical plug is? Yes, it's plugged in.
 

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Code 85 CANP solenoid - The Carbon Canister solenoid is inoperative or missing.

Revised 11 –Jan_2015 to add warning about vacuum leaks due to deteriorated hose or missing caps on vacuum lines when the solenoid is removed.

Check vacuum lines for leaks and cracks. Check electrical wiring for loose connections, damaged wiring and insulation. Check solenoid valve operation by grounding the gray/yellow wire to the solenoid and blowing through it.
The computer provides the ground for the solenoid. The red wire to the solenoid is always energized any time the ignition switch is in the run position.

If you disconnected the carbon canister and failed to properly cap the vacuum line coming from under the upper intake manifold, you will have problems. You will also have problems if the remaining hose coming from under the upper intake manifold or caps for the vacuum line are sucking air.

Charcoal canister plumbing - one 3/8" tube from the bottom of the upper manifold to the rubber hose. Rubber hose connects to one side of the canister solenoid valve. Other side of the solenoid valve connects to one side of the canister. The other side of the canister connects to a rubber hose that connects to a line that goes all the way back to the gas tank. There is an electrical connector coming from the passenger side injector harness near #1 injector that plugs into the canister solenoid valve. It's purpose is to vent the gas tank. The solenoid valve opens at cruse to provide some extra fuel. The canister is normally mounted on the passenger side frame rail near the smog pump pulley.



It does not weigh but a pound or so and helps richen up the cruse mixture. It draws no HP & keeps the car from smelling like gasoline in a closed garage. So with all these good things and no bad ones, why not hook it up & use it?


The purge valve solenoid connector is a dangling wire that is near the ECT sensor and oil filler on the passenger side rocker cover. The actual solenoid valve is down next to the carbon canister. There is about 12"-16" of wire that runs parallel to the canister vent hose that comes off the bottom side of the upper intake manifold. That hose connects one port of the solenoid valve; the other port connects to the carbon canister.

The purge valve solenoid should be available at your local auto parts store.

Purge valve solenoid:



The carbon canister is normally mounted on the passenger side frame rail near the smog pump pulley.
Carbon Canister:





Check out the links below; there is a lot of good information for free…

Diagrams courtesy of Tmoss & Stang&2birds

Vacuum diagram 89-93 Mustangs


See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring; http://www.veryuseful.com/mustang/tech/engine/ Everyone should bookmark this site.

94-95 Mustang wiring diagrams
http://www.veryuseful.com/mustang/tech/engine/#95-95Diagrams

Complete computer, actuator & sensor wiring diagram for 91-93 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/91-93_5.0_EEC_Wiring_Diagram.gif

Complete computer, actuator & sensor wiring diagram for 88-91 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel, alternator, A/C and ignition wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

O2 sensor wiring harness
http://www.veryuseful.com/mustang/tech/engine/images/mustangO2Harness.gif

Vacuum diagram 89-93 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg

HVAC vacuum diagram
http://www.veryuseful.com/mustang/tech/engine/images/Mustang_AC_heat_vacuum_controls.gif

TFI module differences & pin out
http://www.veryuseful.com/mustang/tech/engine/images/TFI_5.0_comparison.gif

Fuse box layout
http://www.veryuseful.com/mustang/tech/engine/images/MustangFuseBox.gif

Mustang 5.0 Lights and Radio schematic, by TMoss:
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxLights-Radio_diag.gif

87-92 power window wiring
http://www.veryuseful.com/mustang/tech/engine/images/mustang87-92 PowerWindowWiring.gif

93 power window wiring
http://www.veryuseful.com/mustang/tech/engine/images/mustang93PowerWindows.gif

T5 Cutaway showing T5 internal parts
http://www.veryuseful.com/mustang/tech/engine/images/5_Speed_Cutaway_Illustrated.jpg

Visual comparison of the Ford Fuel Injectors, picture by TMoss:
http://www.veryuseful.com/mustang/tech/engine/images/Ford_Injector_Guide.jpg

Convertible top motor wiring http://www.veryuseful.com/mustang/tech/engine/images/mustang88VertTopMotorCkt.gif

Engine mounted fuel injector harness
http://www.veryuseful.com/mustang/tech/engine/images/mustangEngineHarness.gif tang/tech/engine/images/mustang88VertTopMotorCkt.gif
 
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