No Heat at idle

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Eightiesrock80

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i replaces the intake manifold and water pump and heater control valve and Themos stat I’m at a loss here I’m ready to get rid of this thing my daughter says Daddy why is it so cold because it’s a piece of $&@“ baby. LOL can anybody please help me. I fix everything but I can’t seem this. I’m pretty sure I got all the air out. Iv seen the air come out many times it seems to be done burping and gargling
 

Bain64

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Have you checked if the heater core was clogged? Check inlet/outlet temps at the hoses, or you could do something similar to this at home core flush If you try the flush, what kind of flow rate do you get ?
 

Bain64

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1. What about inlet/outlet temps of the hose just on engine side of the firewall? Does one hose feel hot and the other only warm?

2. What ambient temperature, and how long does it take to warm up?

3. Is the fresh air vent open or is it recirculating?
 
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Eightiesrock80

Eightiesrock80

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When I’m driving down the road it’s super hot. Hoses are hott to the touch it warms up quickly but not the heat the gauge shows at half pretty quick to average. It doesn’t seem there’s anymore air in coolant. Were are the fresh air vents that recirculate. I didn’t know about this. Is it possible to heater control valve could be closing at idle at red lights because of a vacuum leak although I never feel anything with that vacuum line it seems to just always stay open
 

Bain64

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The fresh air vents come in at the wiper cowl, directly behind the glove box.

Do you have the automatic HVAC controls? I've found it is always in fresh-air mode by default with the EATC. To get recirculate mode, and ultimately much better interior heat, press the forward heat button, or forward & floor heat, then press the recirculate button (picture of car with bent 180 degree arrow).

Moving from my Marquis to the Expedition, I thought I had a bad heater core; however I flushed it and found good flow. I found a couple things though, first is that the 5.4L coupled with a larger interior space greatly increased warmup time as composed to the 4.6 Marquis, but also that to get decent heat it must be in recirculate mode. I hope this helps.
 
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Eightiesrock80

Eightiesrock80

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Yah it’s digital hvac system automatic. I noticed that when I opened the d-gasser cap on the over flow sometimes a ton of bubbles will come out and sometimes non. I felt the heater core hoses in and out and I noticed that one was hot and one wasn’t so hot the Inn was hot but the other wasn’t but when I start moving with the car the heat gets very very hot. I think I need to do another reverse flush on the heater core
 

Adieu

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I think thats just how it works, idling to operating temps takes forever.....give her a couple long revs in park and it'll heat up much faster
 
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