Current time: 11-21-2017, 07:03 PM Hello There, Guest! (LoginRegister)


 
Thread Rating:
  • 0 Votes - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
How too: Keep AC from cycling to dash???
09-21-2017, 11:44 PM
Post: #1
How too: Keep AC from cycling to dash???
Can anyone tell me how to keep the AC from automatically cycling to the dash from the vents when the car is pulling or down shifting? I'm mostly annoyed by this and suspect it's a fuel economy thing. Thanks in advance.
Find all posts by this user View This User Garage
Like Post Quote this message in a reply
09-22-2017, 03:45 PM
Post: #2
RE: How too: Keep AC from cycling to dash???
What do you mean by "cycling to the dash from the vents"?
There is an A/C cutout relay that cuts the A/C just while going WOT, but that doesn't sound like your problem.
[Image: 7082f310-ddf0-45a9-9fc0-153a7ca0a8ce.jpg]
1989 Country Squire - needs more air
2005 CV Sport
SW full exhaust, Heinous control arms, Hawk pads, Powerslot rotors, Addco swaybars, BBK TB, Accufab plenum

Panther, Ford, Crown Victoria, Mercury, Grand Marquis, Marauder, Lincoln, Town Car, Police Interceptor, P71, CVPI, LX Sport, LX, LS, GS, Signature, Limited
Find all posts by this user View This User Garage
Like Post Quote this message in a reply
[+] 1 user Likes BlackVic_P71's post
09-23-2017, 09:41 AM
Post: #3
RE: How too: Keep AC from cycling to dash???
I mean when the air is on and the car is under a heavier load (think driving up a mountain) the ac changes from blowing out the dash vents (that would hit u in the face) to the fan blowing air out the defrost vents (that hit the windshield). I think you are right. Ac cut out relay. Now where is the located so I can yank it out. Will that cause problem that you know of? Or just worst fuel economy.
Find all posts by this user View This User Garage
Like Post Quote this message in a reply
09-23-2017, 10:36 AM (This post was last modified: 09-23-2017 10:38 AM by BlackVic_P71.)
Post: #4
RE: How too: Keep AC from cycling to dash???
It sounds like what's happening is vacuum related, when vacuum increases the door is automatically changing from vent to defrost.
the A/C cutout relay is with the other relays on the passenger front fender just behind the headlights, it should be marked as to which is which. You've got the horn relay, A/C cutout relay and the fuel pump relay there.
The cutout relay is there to free up a little power for when you go WOT, it frees up the A/C compressor pulley so that it doesn't drain power off the engine when it's trying it's best to go fast Wink
[Image: 7082f310-ddf0-45a9-9fc0-153a7ca0a8ce.jpg]
1989 Country Squire - needs more air
2005 CV Sport
SW full exhaust, Heinous control arms, Hawk pads, Powerslot rotors, Addco swaybars, BBK TB, Accufab plenum

Panther, Ford, Crown Victoria, Mercury, Grand Marquis, Marauder, Lincoln, Town Car, Police Interceptor, P71, CVPI, LX Sport, LX, LS, GS, Signature, Limited
Find all posts by this user View This User Garage
Like Post Quote this message in a reply
[+] 4 users Like BlackVic_P71's post
09-23-2017, 11:58 PM
Post: #5
RE: How too: Keep AC from cycling to dash???
Thank you very much.
Find all posts by this user View This User Garage
Like Post Quote this message in a reply
09-25-2017, 04:40 PM
Post: #6
RE: How too: Keep AC from cycling to dash???
Thats the begining of a bigger vacuum leak in the back of the AC header unit. The digital ones have a vacuum valve buried deep in the electronic guts, and in that valve theres a tiny o ring that fails in time.

So you can either:

1. Live with one windshield vents

2. Shell out big bucks for a new header unit (if you can find one)

3. Tear open the back and replace that Oring, then put back the circuit boards (they have to be ripped away so you have to improvise a way to mount them, just mechanical connections, since the electronics should still remain hooked up by wires and connectors)

I did option 3 once and it worked fine. In fact its still in the car now. I still have about 499 O rings left (since they only sold them in packs of 500). But I also bought a brand new OEM header unit to have as a spare. Somehow a shipping error made them send 2...or 3...So yeah, I stock pile them like a squirrel with acorns lol

If you go with option 3, here are the dimensions for the Oring

5/32 Inner diameter

9/32 Outer diameter

1/16 width of the Oring itself. If you do a search you can find it. I found them on Amazon years ago, so you may find them in smaller packs.

Hope this helps.

Al
2004 Crown Vic LX Sport (currently with a booboo and totaled)
1972 Lincoln Continental 1 of 1
1973 Lincoln Continental Saved from the crusher
2014 Chevy Camaro
2007 Crown Vic P71 SAP (officially gone, but its parts still clutter my place)
Find all posts by this user View This User Garage
Like Post Quote this message in a reply
[+] 2 users Like castrosua's post



Forum Jump:


User(s) browsing this thread: 1 Guest(s)

PantherBB.com
Copyright 2012-2015 - All Rights Reserved.

Images, graphics and data contained in this forum are the properties of the contributing members, or PantherBB.com
and may not be used without expressed written consent.
PantherBB.com
is not affiliated with the Ford motor company.