Question about 1981 Ford F 150

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1981 Ford Ranger Full Size 4X4 Heater Problem

My switch broke inside the heater control unit a few days ago and the heat only comes out of the floor vents and I canot defrost my windows. can I just switch a couple of the vacume lines, I would rather have the defroster working than anything else so the windows dont fog up.



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Your switch should have a few cables behind it if you can slide out your radio you can reach them to change it to fefrost easly

Posted on Feb 04, 2009

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bad hacks, your car is not stock
now you get to find someone that wants to touch a hacked up car.
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My heater does not blow in floor in a dodgeram 1500

the heater vacuum motor and lines needs to be checked.Also get the blend door checked.



As per your problem mentioned. There are few solved help links to troubleshoot these problems. Go through the list and Click the link below:----

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Nov 28, 2012 | Cars & Trucks

1 Answer

Here water moving in the heater when I start my 99 ford ranger. Goes away when I drive a few blocks. Sometimes I have no heat also?

It's not uncommon fot it to take several fill ups to get all the air out of the cooling system and the heater is usually the main culprit. I always turn the heater on full blast when I refill a cooling system and run the engine long enough to make sure the coolant is circulating in the heater. This is your most likely culprit.Have you checked the coolant level in the overfow bucket? It should be at the full line on the side. If not, then top it up and replace the cap. Even if it is full replace the cap but leave it loose. Drive with the cap loose for a few days and the heater on full. Check the coolant level daily and top up as necessary. After a few days you should have continuous heat. Then you can tighten the overflow cap. Hope this helps.

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check the hoses going into heater core. are they hot with heater on! if not make sure you have a proper amount of coolant in it. if coolant is ok and all is fine. change thermostat. good-day ! if hoses are not hot its a possibility, that the thermostat is sticking closed and not letting hot coolant through system.

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1 Answer

My heat only blows out the defrost even if the switch is on the floor or the middle vents? 1997 Ford Ranger 4 cyclinder.

The system defaults to defrost when it has no vacuum supply from the engine. check the plastic vacuum line from the engine intake manifold to the heater control panel. Especially look at the rubber hose that connects the line at the engine. If that;s good, follow it thru the fire wall and see if there are any tees, etc where it could leak. Listen for a vacuum leak at the mode control switch. Could leak at the connection or inside the switch. Please let me know if you get stuck or have any questions.

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check antifreeze level make sure its full with antifreeze and not just water if full check heater core for leaks see if it is antifreeze on the passenger side floor

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1 Answer

Problem with air not coming out of vents.

Check for a vacum leak from the engine to the a/c.The color of the hose is black. Also check if the heater control valve hose is unplugged. If you have vacuum the it sounds like the door for the vent/floor/defrost is broken.

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1 Answer

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Double checking, does fun shut off when switched to heat instead of defrost?

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I've had 2 Astros. A 1993 and a 1994, and had a problem with the heat/AC on both of them. They blew only air through the defroster no matter where I set the control, heater, A/C, floor or vent.

Both times the problem was with the VACUUM hoses in the engine compartment. The hoses had become dry, brittle and then cracked. The hoses are black tubes about the size of a drinking straw, and about 12" to 14" in length. Look for hoses that are hanging loose, they usually break off from junctions where 2 or 3 lines come together.

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My Ford ranger does this too. It's been a while since I read on this but if I'm not mistaken I think this is normal.

Jul 14, 2008 | 2001 Ford Ranger Regular Cab

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