No heat

[Joshbaker]

Ok so i havent used the heat since last winter and went to use it yesterday and got no warm air. Just cool air. Thought it might have had something to do with the coolant filter so i changed that and still no heat. Any ideas as to where to look? Im going to feel the heater hoses after i drive home today and see if they are warm. According to the scangauge my ECT stays right around 198.

 

[Smokenblack]

Do you have automatic temp control? Check and make sure the temp control motor behind the glove box is opening the door for the heater core. You can also try to recalibrate it.

 

[Tonka350]

there are a few parts that I have read that cause this...
blend door actuator
blend door switch
temperature actuator

if you look at rockauto.com they have everything to redo the entire heating system for like $250.00 that's where I'm headed so it's all new with no issues.

Chad

 

[Joshbaker]

It's an xlt so just normal temp nob.

 

[Joshbaker]

Finally got a chance tonight to go out and look at the truck some more. It looks like their is some valve on the top heater hose that has a vacuum line going to it (not sure what it is called). Well when i push the valve open (assuming im pushing it open) i can see coolant flow in the degas bottle. But it doesn't move on its own. Im thinking this is my problem. Anybody know what this part is called?

 

[Tonka350]

Josh, I believe what you're referring to has an inlet and an outlet and is the HEATER CONTROL VALVE....looks like a disc on top with a vacuum hose attached and an inlet and outlet pipe.

Chad

 

[Joshbaker]

Yea that sounds like it to me. Now i just need to figure out if its the actual problem or not.

 

[Joshbaker]

Well the valve is working as it should i just cant seem to get anything but cold air???

 

[04stroker]

Do you happen to get any heat if you have it turned on and give it heavy throttle?

 

[Joshbaker]

Nope. Cold air. It's like the nob that controlls hot/cold air doesn't work.

 

[Mdub707]

Mine was always like this too... when it was low on coolant.

 

[Joshbaker]

Coolant is a bit low. going to fill it back up and see what it does.

 

[Joshbaker]

filled it up and still no change. The temp doesnt change at all when you move the dial. how hard is it to change the dial.

 

[Joshbaker]

does anybody know if this is the part that controls blower speed or temp?

 

[4.0l sahara]

That is the switch on the dash for blower speed.

 

[4.0l sahara]

Are both heater hoses hot? Does your truck have the vacuum controlled flow valve in one heater hose?

 

[Joshbaker]

It did until last night. I tool the flow valve out because i thought it might be broke on the inside. Its still hooked up to the vacuum line just not hooked up to the coolant lines anymore. Im thinking its the temp dial in the cab since the blend door accuator is working and everything else is working just cant change the temp of the air being blown in the cab.

 

[Vengeance]

I am having a similar issue, except mine will begin to blow hot air, and then it will go cold after a couple of miles driving. The blend doors are working fine, zip tied the valve on the heater hose open, no hot air. Any suggestions? Heater core plugged up?

 

[psdguy95]

Clogged heater core maybe?

 

[Joshbaker]

Well Im pretty sure its a clogged heater core. I will be trying the CLR method of flushing it this weekend. Ill let yall know how it goes.