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Heating problems! ITS COLD!

2226 Views 33 Replies 8 Participants Last post by  6ohPowersmoke
Ok guys so here are my issues. I probabaly should have looked into this before the cold weather but it hadn’t bothered me until temps have been in the 20-30 range.

problem #1 my heat is not working kind of. It was working intermittently the past few months but has gotten worse (or so it seems) while working intermittently it would range from blowing cold to luke warm to hot and all in between with no rhyme or reason. I have checked me degas bottle and the coolant level seemed to be a little lower than normal but not drastically lower than my line. (I checked it after a cold soak) it seems like it wouldn’t blow any type of warm air until the truck was up to temps then would intermittently blow warm. It also seems to blow warmer if I have it set on 80 compared to 90. Could the slightly low coolant level be the cause? Am I correct with what the coolant level should be after a cold soak? My degas bottle has a molded line and I have a sharpie line below that

problem #2 my driver seat heater does not work. Passenger works great and gets hot. Drivers seat has the red light on the button come on but no heat. I have read it could be a bad relay, I do not hear a relay click On when I hit the driver button. Wheee is the relay? How do I change it?

also to note, I have not noticed any coolant leaks so the drop in coolant level, although minor, has me puzzled.

it is deleted and studded with a coolant filter on there
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Also just to note, my A/C during the summer was also kind of spotty. It would blow but not also very cold and would take a while to blow cold. Not sure if it’s related or not.
Are the heater hoses warm soon after you start the truck? and does the heater put out warm air then?

Your blend door actuator could be bad, if the hoses are hot but not warm air in the heater
if the hoses are still not warm after several minutes after start, then you may have a different problem
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Do you mean the hoses leading into the heater core?
Well Ya, ...aren't you asking about the heater?

problem #1 my heat is not working kind of. It was working
Yea, I’ve just went down a lot of rabbit holes with this reading a lot about heater core, radiator, hoses, coolant, valves etc and it’s all gotten jumbled in my head so I just wanted to make sure. I’ll check those on start up in the morning
The hose on the RH side where it connects to the water pump is the supply
Then runs back to a vacuum valve before entering the heater core
Look for heat there first

The vacuum valve should be in the extended position -- it is only closed when the controls are OFF and Max AC
Soon as you feel heat in the supply line, it should also be in the return -- wait till the heat feels pretty warm to the touch -- then go feel the heater air

You can pop the plug off the heater fan, and key on -- if it is quiet there, you should hear the blend door motor as you operate the temperature -- should move smoothly with no clicking
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Heater valve (vacuum valve) getting stuck closed is my first thought. You can move it manually by just squeezing the cylinder part towards the rear. I had some spotty heat and AC, along with a nice coolant leak mixing with grease and looking like oil. I chased my tail around and I felt around and noticed there was a crack on the heater valve and it didn't move very well.

Checking for a hot supply hose should be able to rule out a water pump or thermostat problem as well.
Your degas cap may not be holding pressure. If it's old I would go ahead and replace it. That will help you find any leaks.
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Ok I started the truck. Waited maybe 3 minutes and felt the hoses. Both were warm but not hot yet by the time I got to work both were much warmer. The vacuum valve stayed in the same position no matter what setting it was on. It was facing the cab of the truck (running parallel with the hose) The heater air did not feel warm after waiting a few minutes but I did not check it when I stopped.

where is the plug for the heater fan? Also my truck doesn’t have the dial style controls it’s the style in the picture below. Does the blend door still work the sane way With this style?

degas cap is as old as the truck I’m guessing so I will replace that for good measure as well

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I guess I did not convey the idea about the hoses getting hot very well -- the point is the heater hoses (especially the supply) get hot first (before anything else) -- By the time you got to work, everything should have been too hot to hold your hand on, for very long -- At that point the heat in the cab should have been good - and the return hose hot as the supply.

The air blend controls function the same on both types -- just one is a knob and the other is digital

The round part on the valve is the air cylinder -- use your finger and move the lever towards the cylinder -- when you let go the lever should spring back out -- be sure the lever is moving to the full extent -- out is ON, in is OFF
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No leaks around the vacuum. It springs back, but it does go back to the starting position. With koeo I tried to listen for the blend door while cycling through different modes (a/c-heat-off) and did not hear anything.

I guess I’ll start there
Replaced the actuator and can’t tell much of a difference. The vacuum valve isn’t moving when I switch from heat to a/c to off. Should it? Also I’ve seen where some trucks have a small vacuum hose on top of that valve. Mine is on the back. Is that correct? Am I missing one?

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Hose in in the correct place -- but as stated before you do not use that valve in the winter -- only OFF and Max AC

Most likely you have other problems in the vacuum system -- we need to address your current problem first
pick up a hand held vacuum pump that has a gauge from someplace like harbor freight or amazon -- for testing , later
does the air flow speed/power seem to be the same in all settings? feet, vs body, ve defrost or does it seem to blow harder on defrost than all other settings?
does the air flow speed/power seem to be the same in all settings? feet, vs body, ve defrost or does it seem to blow harder on defrost than all other settings?
I haven’t noticed there being a difference but I’ll be on the look out for that tomorrow
Hose in in the correct place -- but as stated before you do not use that valve in the winter -- only OFF and Max AC

Most likely you have other problems in the vacuum system -- we need to address your current problem first
pick up a hand held vacuum pump that has a gauge from someplace like harbor freight or amazon -- for testing , later
I will have a better idea if the actuator worked or not in the morning 1plus drive at 5am in 28 degree weather should give me a good idea. If that’s not the culprit what would be next?
On the seat heater..... Your pad is probably bad. The relay controls both sides, so if it's the relay, neither would work.
I took advantage of the bad heating pad and "upgraded" to 5 way adjustable seat heaters, that also have pads for your back.

Sent from my Redmi Note 9 Pro using Tapatalk
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Ok here’s the update. It was definitely warmer this morning. I had it on max temp and max fan. I wouldn’t consider it hot but it was warm. I guess that better than nothing. Any reason it wouldn’t be getting as hot as it should?

I was hoping there was a relay on both seats and maybe that was the problem with the drivers. I don’t have anyone ride with me much. Are the seat elements interchangeable? Might just switch them
Also it only felt the warmest after the truck was up to temp and I was going down the highway at 75. Once I got off the interstate and slowed down it cooled down and was blowing more luke warm air
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