Common questions

Why is my Ford F350 AC only blowing through defroster vents?

Why is my Ford F350 AC only blowing through defroster vents?

You may have a bad fuse, pump or broken vacuum line. They also use vacuum to operate the locking hubs on 4×4 versions, a leak in parts of that system can rob all the vacuum. The diesel version of these trucks use an electric vacuum pump, without vacuum the heater defaults to the defrost for safety.

What kind of truck is a 2001 F350 DRW?

Trucks a 2001 F350 DRW (in my signature below). The 4×4 worked perfect since I got it and ALL winter. Today I went to pick up the plow setup for my 02 F450 (that I just purchased on monday) and had some issues. The guys got a big lot where he keeps his equipment, plows and trucks.

When does a Ford car default to defrost?

It defaults to defrost when the motor/vacuum that turns the vents fails. Its vacuum controlled. The vacuum lines are under the hood, but I have no idea where. Passanger side fire wall over the valve cover. Black cylinder with a plastic nipple.

Is the air still coming through the defrost vents?

Air still coming through defrost, visually inspected lines going to hubs, look fine. The air coming through the defrost is AC if I put it on AC setting and not AC if I turn it to regular air. I haven’t had weather to see if the defroster setting would work, do you guys know if it would and could this vacuum issue compromise my 4hi or 4lo?

You may have a bad fuse, pump or broken vacuum line. They also use vacuum to operate the locking hubs on 4×4 versions, a leak in parts of that system can rob all the vacuum. The diesel version of these trucks use an electric vacuum pump, without vacuum the heater defaults to the defrost for safety.

Trucks a 2001 F350 DRW (in my signature below). The 4×4 worked perfect since I got it and ALL winter. Today I went to pick up the plow setup for my 02 F450 (that I just purchased on monday) and had some issues. The guys got a big lot where he keeps his equipment, plows and trucks.

Why is my 1999 F350 4×4 not engaging?

1999 Super Duty trucks with electronic shift-on-the-fly 4WD have a problem with 4X4 not engaging properly or engaging when it shouldn’t. There are both temporary and permanent fixes for the problem.

Is there a vacuum leak in my Ford Super Duty?

Now my heater will not work at all, just the defrost, and on top of that my 4WD is not engaging. These are classic signs of a vacuum leak on 1999-2004 Ford Super Duty Trucks. On these trucks the hubs are engaged using vacuum. A lot of folks complain about having a lot of problems with these vacuum operated hubs.

Why does my heater not change from defrost vents?

Re: Heater/ac will not change from defrost vents to any… Failure of mode and/or blend door operation most often tends to be vacuum supply issues. If there is no operation of the doors at all (switching from defrost-floor-vent) then verify vacuum supply on the vacuum line at entry of the firewall (it’s easiest to get to).

Can a Ford F350 heater change to any other vents?

Heater/ac will not change from defrost vents to any other vents on my Ford F350. AC works but comes out of defrost only Clicking this will make more experts see the question and we will remind you when it gets answered. You can’t post conmments that contain an email address. An expert that got 10 achievements. An expert that got 5 achievements.

How does the air vent work on a defroster?

The vent control system for the defroster in integrated into the operation of all temperature controls and uses forced air provided by the blower motor. On newer cars the vent direction and temperature controls are operated by a series of 3 or 4 electrical actuator motors which are adjusted by the climate control module.

Heater/ac will not change from defrost vents to any other vents on my Ford F350. AC works but comes out of defrost only Clicking this will make more experts see the question and we will remind you when it gets answered. You can’t post conmments that contain an email address. An expert that got 10 achievements. An expert that got 5 achievements.

Why is my Ford F-250 stuck in defrost?

The suction system not only controls air zone valves, but also 4X4 activation. Typical vacuum leaks, like old lines are often the problem, but there is one last component that everyone participating on automotive help forums fails to mention when troubleshooting this trouble prone system, the electric vacuum solenoid valve. Loading…

What causes air vents to stay in defrost position?

If you have an older car then the defroster system is controlled by using vacuum supplied by the engine. Lift the hood and inspect the vacuum hose or tube that leads from the intake manifold to the passenger’s side firewall. The image below shows a typical line break which causes the vents to stay in the defrost position.

What should I do if my heater does not change from Defrost to vent?

If there is no operation of the doors at all (switching from defrost-floor-vent) then verify vacuum supply on the vacuum line at entry of the firewall (it’s easiest to get to). If no vacuum, trace the line back to the vacuum supply. You didn’t state if we’re dealing with gas or diesel engine.

Air still coming through defrost, visually inspected lines going to hubs, look fine. The air coming through the defrost is AC if I put it on AC setting and not AC if I turn it to regular air. I haven’t had weather to see if the defroster setting would work, do you guys know if it would and could this vacuum issue compromise my 4hi or 4lo?

It defaults to defrost when the motor/vacuum that turns the vents fails. Its vacuum controlled. The vacuum lines are under the hood, but I have no idea where. Passanger side fire wall over the valve cover. Black cylinder with a plastic nipple.

Why does my Ford PowerStroke blower quit working?

Well the “NEW” blower motor is as weak, or weaker, than the original 13 year old Ford blower. That isn’t the problem. It’s been on the truck for 1 day and it’s going back to RockAuto. Today in the 90 degree heat, it decided to just quit spitting anything out of the vents altogether.

The suction system not only controls air zone valves, but also 4X4 activation. Typical vacuum leaks, like old lines are often the problem, but there is one last component that everyone participating on automotive help forums fails to mention when troubleshooting this trouble prone system, the electric vacuum solenoid valve. Loading…

Can a / C only blow out of defrost vent?

Problem is no matter what setting I put it on it still blows out of the windshield defrost vents. Has anyone had this problem before?

Why does my Ford truck have no air?

Our trucks are also notorious for the Auto hubs not engaging 4×4 because of vacuum. The vac lines run all the way to the front hubs. Those lines will degrade and cause these issues also. The hubs say auto/lock on them.

How to change the defrost vent on a car?

Just Follow the plastic vacuum line which comes out of the pass side top rear of motor close to the alternator. You can easily see it once you pop the hood. Follow it over the brake master cylinder and then going to the front of the motor. Be careful not to pull on the vacuum lines too hard as they are brittle and crack very easily .

Why does AC blow cool air through defroster vents?

No matter what setting it’s on, or speed, it all comes out the defrost vents. So if I turn the AC on it will eventually blow cool air through the defroster vents while I’m driving, if I come to a stand still the AC air coming through the defroster vents will not be as cool, more musty.

If there is no operation of the doors at all (switching from defrost-floor-vent) then verify vacuum supply on the vacuum line at entry of the firewall (it’s easiest to get to). If no vacuum, trace the line back to the vacuum supply. You didn’t state if we’re dealing with gas or diesel engine.

Where is the vacuum hose on a 1999 Ford E150 van?

This 1999 Ford E150 van came in with the complaint that the a/c would only blow out of the defroster. The mode actuators in this vehicle are vacuum controlled so checking vacuum is the first point in the diagnostic routine. There is a vacuum hose splice connector under the hood on the passenger side of the vehicle.

What kind of car wont blow out the vents?

AC wont blow out of vents. 2003 Ford E150, E250, E350. Ford F150, F250, F350, 1997, 1998, 1999, 2000 – YouTube If playback doesn’t begin shortly, try restarting your device.

Why does AC come out the dash vents?

The factory vacuum check valve is very hard to get to. So i bypassed it. Now it is working like it should and ac comes out the dash vents. I do not have a vacuum reservoir installed i will have to see if i will need to add it later. Don’t forget to like, comment, share and subscribe to my channel. Loading…

Our trucks are also notorious for the Auto hubs not engaging 4×4 because of vacuum. The vac lines run all the way to the front hubs. Those lines will degrade and cause these issues also. The hubs say auto/lock on them.

Can you replace the windshield on a Ford F350?

Ford F Series F350 Windshield Replacement: Multiple Competitive Instant Auto Glass Replacement Quotes. Any and all trademarks, service marks or copyrights associated with FORD are the intellectual property rights of the manufacturer or the manufacturer’s affiliates, and Honex disclaims any intellectual property rights in the same.

How much does it cost to replace glass on a Ford F Series F350?

How much does it cost to replace glass on a Ford F Series F350? The cost of replacing your Ford’s Auto Glass depends on a number of factors, including: Side Glass (Door Glass, Vent Glass, Quarter Glass) Back Glass (Also called, Rear Windshield or Rear Glass) Technology Options on your glass, such as rain sensors, adaptive cruise control, etc.

When did the Ford F 350 become Super Duty?

From 1990-1997, the F-350 was quite similar to the F-150 but with added strength for more towing. In 1999, the F-350 became part of Ford’s Super Duty line.

Why does my C280 blow air from the vents?

My C280 seems to have developed a bad actuator motor MB calls it a stepper motor in the plumbing vent work. All air blows from defrost and side vents.

Why does air blow through the defrost vents?

When you place the Climate into AUTO it opens the center flap and a refresh/recirc flap, but the refresh/recirc flap closes after a min, that’s why you get air through the center vent for a min while you center flap is stuck closed.

Why does my vacuum not defrost the dash?

The vacuum runs both the heater damper door and the 4×4 automatic hubs. Usually when the vacuum pump dies or a hole gets pinched in the line, the Damper door will default to the Defrost position. So you can not get air to the dash or floor vents. Its a safety feature to make sure you can see out the windshield in the event of vacuum failure.

Where are the vents on a Ford van?

The vents that are on the front of the dash, the ones you can adjust to hit you, they “sometimes” work. I bought the van last week. They told me the A/C did not work, but it did, for a few days.

What to do if your AC heater does not change?

Follow it over the brake master cylinder and then going to the front of the motor. Be careful not to pull on the vacuum lines too hard as they are brittle and crack very easily . It will T off and go down into the fender. Plug it off with a screw a little smaller than the line and use some silicone to hold the screw in.

Re: Heater/ac will not change from defrost vents to any… Failure of mode and/or blend door operation most often tends to be vacuum supply issues. If there is no operation of the doors at all (switching from defrost-floor-vent) then verify vacuum supply on the vacuum line at entry of the firewall (it’s easiest to get to).

What to do if your Ford vent control is stuck?

Ford Vent Control Stuck on DEFROST? Here is how to FIX it. Simple Hack to save Money! – YouTube

How to replace your Ford F-250 blend door actuator?

Here’s how to replace your blend door’s actuator and ensure you get hot and cold air when you want in your Ford F-250 or F-350 Super Duty. This article applies to the Ford F-250, F-350 Super Duty (2005-2014). The blend door actuator is responsible for controlling the hot and cold air mixtures in your Ford F-250 or F-350 Super Duty.

Why is my defroster not working on my car?

A control switch on the dash can fall apart allowing the vacuum to escape and not reach the servos. A defroster can also fade when traveling up a hill but then return once the grade is overcome which is a signal the vacuum check valve has failed.

The vents that are on the front of the dash, the ones you can adjust to hit you, they “sometimes” work. I bought the van last week. They told me the A/C did not work, but it did, for a few days.

Why does my AC heater default to defrost position?

Sounds like the main problem is a vacuum leak. When you loose vacuum the ac/heater will default to the defrost position. Check for vacuum leaks first. Get a copy of the appropriate sections of the shop manual. It should have a schematic that describes the flap positions at the different control positions. I also suspect it’s a vacuum issue.

The factory vacuum check valve is very hard to get to. So i bypassed it. Now it is working like it should and ac comes out the dash vents. I do not have a vacuum reservoir installed i will have to see if i will need to add it later. Don’t forget to like, comment, share and subscribe to my channel. Loading…

This 1999 Ford E150 van came in with the complaint that the a/c would only blow out of the defroster. The mode actuators in this vehicle are vacuum controlled so checking vacuum is the first point in the diagnostic routine. There is a vacuum hose splice connector under the hood on the passenger side of the vehicle.

Why is the defrost not working on my GM Truck?

My airflow is stuck in the floor position no matter what setting is switched on the dash vent switch. I can’t get defrost or dash vent air to work. Fan settings do work. Also, there is no light coming on when the AC button and/or the recirculating buttons are pushed.

How to fix Ford AC defrost only-vacuum vent leak?

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Ruth Doyle