EVAC Purge Valve plumbing...

Discussion in 'SN95 4.6L Mustang Tech' started by dsmithwc04, Dec 20, 2011.


  1. dsmithwc04

    dsmithwc04 Member

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    I have a 97 Cobra and cant figure out what the PO did to the vacuum plumbing. I see where many vacuum lines run into various "T" fittings but the purge valve is not connected into anything. I smell fuel vapor when inside the car and think that this is comming from the valve purging fuel vapor from the cannister straight into the space under the hood instead of into the intake manifold. Anybody who could post some pics of their vacuum plumbing around the intake manifold and firewall would help this guy out a bunch!
  2. dsmithwc04

    dsmithwc04 Member

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    So nobody has any way to get a picture with some help on my EVAC system. I doubt this. Come on peeps, help a fellow Cobra owner out!
  3. wmburns

    wmburns SN Certified Technician

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    Don't have a Cobra. But on the 98 and older Mustangs, there should be a vacuum line from the the charcoal canister to the purge solenoid. From the purge solenoid the line goes to the purge flow sensor. From there the line goes to a vacuum port on the intake. This is the source of engine vacuum.

    The charcoal canister is located inside the right hand fender well for the 96-98 MY.

    The fact that your purge solenoid does not have a vacuum line on it, would mean that the charcoal canister is vented into the air.

    If you still need diagrams, a Ford factory service manual may provide the help needed. If interested in getting a copy for yourself, I maybe able to help. PM if interested.
  4. dsmithwc04

    dsmithwc04 Member

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    wmburns, I should have known you would be the only one to help out. I already got a copy of the Ford Service Manual from you. This was one of the reasons I got it but couldn't see a detailed diagram in there. I think my vacuum lines were messed with near the firewall and can't seam to figure out what goes where. There is no line from the purge valve which I believe goes to the intake manifold. The problem is there is no open spot for it to go.
  5. dsmithwc04

    dsmithwc04 Member

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    Surely somebody has some info that they could then spend 3 minutes, grab a picture and help a fellow 'stanger our?
  6. wmburns

    wmburns SN Certified Technician

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    There is a diagram of the EVAP plumbing in the Ford service manual Section 03-13: Evaporative Emissions. Look under "Evaporative Emission Canister Purge Valve".

    The diagram is of the 3.8 engine but the concept is the same. The diagram shows the order of the parts and their relative locations. Seems to me the only thing you are missing is the engine vacuum source.
  7. dsmithwc04

    dsmithwc04 Member

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    Am I rude to feel dissapointed that not one person who owns a 96-98 Cobra won't take a snapshot of where the vacuum lines are supposed to be connected? Really, 3 minutes from snap to upload?
  8. wmburns

    wmburns SN Certified Technician

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    Try this. Go to 1997 Mustang workshop maual, group 03: engine, section 03-01C engine 4.6 (4v).

    Under "IN-VEHICLE SERVICE", click on "Engine Components". This will bring up an exploded diagram of the 4V motor. The 4V main vacuum hose assembly is part number 40. Note the "T" fitting in the upper right. Likely one side goes to the AC damper controls. The other side goes to the EVAP system.

    40 9E498 Main Emission Vacuum Control Connector
  9. dsmithwc04

    dsmithwc04 Member

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    Thanks burns but I can't quite figure it out by the page. It isn't quite detailed enough.
  10. dsmithwc04

    dsmithwc04 Member

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    Okay, figured it out. The vacuum line from the intake that was supposed to be connected to the evap purge valve was connected to the other vacuum lines in a rigged "t" setup and the purge valve was left open. Again this is another reason to not buy a car from a hillbilly in the hills of kentucky...
  11. cobrett

    cobrett New Member

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    So, did the fuel smell go away?

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