Heater question

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Dec 16, 2008 | 08:27 PM

chaser1602

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From: sanford

Heater question

2000 f150,Heat is not to warm and it switches to a/c back and forth.Happens in all positions and fan settings

Dec 16, 2008 | 09:33 PM

steve(ill)

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i dont know what switches to AC means. if the air is cold and not hot, then you need to look at the temp gauge. if the truck is running very cold, then the thermostat is stuck and will not warm up the antifreeze. if the temp gauge is hot or jumpy, and no heat, then the antifreeze level is too low, check the plastic tank.

Dec 16, 2008 | 10:56 PM

SSG VA BEACH

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From: va beach

Also check the heater core housing and the damper cables that go in there.

Eric

99 F150

Dec 17, 2008 | 05:13 AM

chaser1602

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From: sanford

Quote:

Originally Posted by steve(ill)

Sorry,I didnt understand it at first also.I should have been more clear.The heat coming out of the vents are not very hot and then the a/c switches on for a couple seconds,then goes back to heat and on and on.It sounds to me like it is stuck in defrost mode.Not my truck and I havent seen it yet,loking for ideas before I take it on

Dec 17, 2008 | 09:44 AM

yetislayer37

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I have a '99 F150 w/ 5.4 and my similar problem seems to be vacuum related. To get heat I drive a few miles to build engine heat, switch to a/c and cold, stop and accelerate from the stop fairly hard. When you feel the heat coming through the vent switch everything to floor and warm then I'm good to go for that trip. This takes less than 50ft. If after 50ft or so and it didn't work, do it again accelerating a little harder. Back in the summer a/c was all fine on the highway but if I came to a stop you could feel the heat kick on. Not a daily driver so this works for me for now.

Dec 17, 2008 | 01:12 PM

SSG VA BEACH

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From: va beach

Uhh say what now ?

Dec 17, 2008 | 01:20 PM

KingRanchMan02

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From: Louisville, Kentucky

This is either a vacuum problem or a blend door problem. There is a vacuum line that goes through the fire wall near the battery that supplies the heater controls. BTW, there are no damper cables used in these trucks. You might want to read this FAQ.

https://www.ford-trucks.com/forums/7...xpedition.html

Good luck!