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Heating problems! ITS COLD!

2236 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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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.
Now that sounds like a slipping water pump. Still have an OEM plastic pump?
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