Air vents not switching

[psdguy95]

The air vents on my truck are stuck on the defrost vents. I tried switching out the dash panel but still got nothing. I took the vacuum lines off the door actuator to see if I was geting vacuum and I didn't feel anything. Shouldn't it pull a good amount of vacuum? I have no idea where to look next. I need this fixed asap.

 

[Arisley]

Look at the vacuum pump, or the vacuum lines going to your 4WD hubs.

 

[psdguy95]

My hubs lock when I put it in 4wd. Those lines are good.

 

[Arisley]

That means it is a line between the pump and the vents. Look under and behind the glove box. There is a connection there.

Good news is that you pump is working.

 

[Zmann]

but He should have felt vacuum when He pulled the line ?

 

[TyCorr]

but He should have felt vacuum when He pulled the line ?

Not if the line isnt hooked up.

To the op, go to the vacuum pump, trace the line that goes to the cab. One goes downward and follows the crossmember down and goes to the hubs to actuate the 4wd. The other line goes into the cab. Start at the pump, work your way in towards the cab. If everything is still hooked up start checking the "vacuum motors". They are the vac. operators with rods that pull/push stuff open/shut. You can test these with a handvac such as the mityvac. If one doesnt hold the vacuum, its junk. That should get you started.

 

[JLDickmon]

yep

 

[psdguy95]

Not if the line isnt hooked up.

To the op, go to the vacuum pump, trace the line that goes to the cab. One goes downward and follows the crossmember down and goes to the hubs to actuate the 4wd. The other line goes into the cab. Start at the pump, work your way in towards the cab. If everything is still hooked up start checking the "vacuum motors". They are the vac. operators with rods that pull/push stuff open/shut. You can test these with a handvac such as the mityvac. If one doesnt hold the vacuum, its junk. That should get you started.

Ok. I will look in the morning.

 

[Tampa450]

Good thread... My 450 is doing almost the same thing.

 

[TyCorr]

Its a common problem. About five threads a year on this. Sometimes you dont.have 4wd or control of.the hvac. Then you have to check for.voltage at the vac pump plug. Check your fuses. If the fuses all.check out, your gem is likely toast. Which also means your windshield is leaking. Another common superduty illness: leaking.windshield glass.

 

[psdguy95]

Ok so heres what I discovered. The black box in between the passenger side battery and the vacuum pump ( not sure what its called ) isn't letting vacuum out. Its getting vacuum from the pump but its not puting out any. I turned my SOF on and I dont get much vacuum at those lines either. Does that mean that box is no good?

 

[Zmann]

try to blow through it using a short hose
it may be cracked ? blocking the exit with your finger and see if you here any hissing ,, or spray soapy water on it and look for bubbles

it called the vacuum reservoir

 

[Zmann]

the esof uses a reduced vacuum signal so don't gauge by anything after the solenoid to the hubs

 

[psdguy95]

I took the vacuum lines off the esof switch and I wasnt getting much. I also just took the "out" side of the vacuum off that box and nothing was coming out.

 

[Zmann]

and that makes little sense lol since the esof ""switch should be"" feed from the reservoir

 

[psdguy95]

Haha. So am I looking at just replacing the box or could there be something else causing it?

 

[Zmann]

I would imagine it's the reservoir ,, you can test it for leaks to verify .. but they do crack

you can bypass it to test the system ,,the pump will just run more

 

[psdguy95]

Ok. Ill test it and see what happens. Thanks man.

 

[TyCorr]

Ok. Ill test it and see what happens. Thanks man.

KOEOff does the pump run? Itll putter like a.fish.tank bubbler. If its not running then you need to get that.squared away. Im not saying it.doesnt work but make sure. Turning the esof knob and.getting a light to come on doesnt mean jack. Im trying.to.help so.dont take this.the wrong.way. Its an easy problem to.throw parts at. Ive been.down this road and helped a couple people personally to.fix.their.

Good luck!

 

[TyCorr]

Oh and summer of 2010 ford.was.getting 247 bucks.for a pump.