Blowing from defrost vents only, 2001 Ford ranger xl

[bailinbailey]

The air only blows out of the defrost vents onto the windshield. I have a brand new climate control, and all vacuum lines are good beneath the hood.
2wd 2001 ranger single cab 2wd 2.5l manual

 

[Dirtman]

Vent is the default setting, so when the actuators fail it will stick in vent mode.

What do you mean you tried a brand new climate control?

 

[bailinbailey]

I bought a module for selecting ac, no ac, head vents, feet, or defrost. It didnt fix it. I am so sick of this truck. So what your saying is the black ball located on fender is not pushing vacuum.

 

[Dirtman]

The selector assemblies rarely fail. You could have a bad vacuum actuator, or a vacuum leak. Start by checking the line from the vacuum resivior to the intake, then check the resivior itself for cracks, and follow the line all the way into the cab. A vacuum gauge would make the process quicker.

 

[1999Mazda Central Florida]

Hey B.I. Bailey: my 1999 Mazda/Ford B2500 manual single cab is doing the same thing but only in "A/C Max" position AND...when I accelerate hard. When on just the "A/C "switch/dial position, cooling is nominal and no bypassing out defrost vent (even with hard acceleration.) The issue you are describing happened to me X3 times and a broken or cracked vacuum line was always the cause, but like you said the lines were good on yours. The issue I'm having now is a real problem since I have not located a broken or cracked vacuum line (like your situation.) I still have A/C though but only in A/C dial position. Does it bypass on the A/C Max dial position AND the A/C dial position, or just the A/C Max position? The vacuum actuator is up behind the glove compartment (at least on my 1999 Mazda/Ford.) I think I'm going to replace the actuator pump which is the vacuum operated cyclinder piston thing that moved the vent/door. I don't think I have a vacuum reservoir (the round ball/bottle,) at least I cannot find it unless it's under the shroud under the passanger side fender. I would just replace it all: reservoir, and actuator pump.
I'll re-post once I replace the actuator piston. I attached a few pics of vacuum actuator pump (which opens/closes the vent door up in the dash.)
Update Oct. 6, 2019: I just ordered the vacuum actuator cylinder pump (connected to the mixer door) I will get to this soon enough, but the question is still: does the 1999 Ranger or Mazda b2500 have the round vacuum reservoir tank (or is that on the earlier model trucks?)
Update Nov. 24, 2019: I removed the radiator & wiper fluid reservoir to see things better. Also, removed the inner plastic fender liner and found the vacuum reservoir (see attached pic.) It was in between the inner fender and the plastic liner...sheesh. Must be a Mazda distinction. Also, sure enough, found a broken grey vacuum line which may be the issue with bypassing to defrost on acceleration (in A/C MAX only.) I will hold off on replacing the vacuum door actuator until vacuum like is fixed to see if it fixes it.

 

[cbxer55]

When the mixer door goes bad or usually, breaks, the same thing happens. I used to have a link to a fix where you remove the glove box, go in through there and put in screws to replace the broken plastic shaft. Can't seem to find it anymore though. Maybe it's on here somewhere.

 

[1999Mazda Central Florida]

The air only blows out of the defrost vents onto the windshield. I have a brand new climate control, and all vacuum lines are good beneath the hood.
2wd 2001 ranger single cab 2wd 2.5l manual

Did you ever get to the bottom of the A/C blowing from defrost issue?

 

[RonD]

Did you ever get to the bottom of the A/C blowing from defrost issue?

It is because there is a vacuum leak in the engine bay

Defrost, panel and floor air flow is directed by Vacuum activated doors
Defrost is the default or no vacuum available selection

In the engine bay, passenger side at the firewall you will see two hard plastic vacuum lines coming out of the firewall
The Grey line goes to the Heater Hose by pass valve, easiest to find
Next to it will be a Black line, this is the Main Vacuum line and the one that gets broken or melted by the exhaust

Find it and follow it
It goes to the Vacuum reservoir, located low down at the front of the engine bay, follow the black line to it
On the vacuum reservoir is another Black line, follow it up to the Intake Manifold, this line is the Vacuum source

 

[JohnnyO]

Blend door actuator went bad or the blend door arm broke. It defaults to the defroster if that happens. Happened on my Sport Trac, blend door arm was broken. Dealer wanted $1600 to replace the whole underdash plenum. I took it to my mechanic for a second opinion and he fixed it for a half-hour labor and a zip tie.

 

[Dirtman]

@JohnnyO The blend door actuator only controls the temp. It just swings the... well... blend door between the heater core side and AC side of the system. It's the thermostat. The vents themselves (floor, defrost, panel) all have vacuum actuators to open and close them.

When a blend door motor fails, you just get stuck in one temp setting wherever the motor decided to break at. Doesn't effect where the air actually flows through the vents.

But yes when the vacuum fails the system defaults to defrost.

 

[1999Mazda Central Florida]

@JohnnyO The blend door actuator only controls the temp. It just swings the... well... blend door between the heater core side and AC side of the system. It's the thermostat. The vents themselves (floor, defrost, panel) all have vacuum actuators to open and close them.

When a blend door motor fails, you just get stuck in one temp setting wherever the motor decided to break at. Doesn't effect where the air actually flows through the vents.

But yes when the vacuum fails the system defaults to defrost.

Thanks man So I may actually have one of two actuator cylinders gone bad? The A/C position works but when in A/C MAX dial position I get bypass to defrost upon acceleration only. Schematic looks like I may have either IMRC Vac. actuator #1 or IMRC Vac. actuator #2 bad. I wonder which actuator is the A/C MAX (IMRC #1 or IMC #2?)