Location and identity of 4x4/HVAC vacuum swithches - Ford Powerstroke Diesel Forum
Please Visit our Site Sponsors
6.0L Problems Forum Having Trouble? Post here

Powerstroke.org is the premier Diesel Truck Forum on the internet. Registered Users do not see the above ads.
LinkBack Thread Tools Display Modes
Old 03-18-2014, 07:06 AM
Powerstroke.org Rookie

Join Date: Mar 2014
Posts: 2
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
Location and identity of 4x4/HVAC vacuum swithches

Hello All:

I am a newbie to the world of diesel, and this forum. Please be gentle with me. I have an 03 EX Limited and have had HVAC only through defrost and no ESOF 4WD drive for some time. Have done research and am well aware that the problem is likely vacuum related. I had a dead Vacuum pump. replaced that it now works. Runs constantly, indicates a leak. Recently I found what is likely another big piece of the puzzle. there is a thin (2mm id +/-) grey fairly stiff plastic vacuum line that comes through the firewall high on the passenger side bundled with a larger (4mm id +/-) black rubber vacuum line. The grey line had apparently fallen of its nipple and melted on the engine block. I have a friend with a 6.0 and he took the attached picture of the unit the grey line attaches to. It is what looks like a vacuum solenoid mounted on the coolant line running to the heater core (picture attached), located on the driver's side and slightly to the rear of the oil fill pipe. The nipple on the front of the switch/solenoid is too small for hose to go on directly. 2 questions; (1) what is this switch/solenoid called; (2) how does the grey plastic hose attach to it (i.e. via a coupler, or did I lose another critical part/end when the grey hose melted and the end disappeared? Your insights and pictures of parts/assembly will be greatly appreciated. Thank you.
Attached Thumbnails
Location and identity of 4x4/HVAC vacuum swithches-pic-switch-solenoid.jpg  

Last edited by Rugger9de; 03-18-2014 at 07:08 AM. Reason: Forgot a detail
Reply With Quote Quick reply to this message
Sponsored Links
Old 03-18-2014, 07:25 AM


Join Date: Oct 2006
Location: winston salem north carolina
Posts: 9,265
Thanks: 0
Thanked 4 Times in 4 Posts
Feedback Score: 0 reviews
the piece is the heater control valve and the grey line hooks right to the nipple on front of it with a rubber vacuum end , I have seen some aftermarket heater control valves be a smaller nipple , may have to fabricate you a piece of line to make it fit

the heater control valve only operates when a/c is on, you can just block off the grey line to make sure that fixes youre issue , and its not that big a deal that its not attached to the heater control valve , you really wont notice the difference
Reply With Quote Quick reply to this message
Old 03-18-2014, 07:29 AM
Powerstroke.org Rookie

Join Date: Mar 2014
Posts: 2
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
Thanks Scuffy. I'll give it a try and we'll see what happens.
Reply With Quote Quick reply to this message
Sponsored Links

Quick Reply

Register Now

In order to be able to post messages on the Ford Powerstroke Diesel Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Thread Tools
Display Modes

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

All times are GMT -8. The time now is 12:30 PM.

Powered by vBulletin® Copyright ©2000 - 2015, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.1
Garage Plus, Vendor Tools vBulletin Plugins by Drive Thru Online, Inc.