No Heat!

[beaglegun]

I have a 97 Ranger. I only get cold air no matter where the temp control is. It switches from defrost, floor, dash,etc. but nothing but cold air. I believe that means I don't have a vacuum problem? Do I have a bad temp control?

 

[Andres629]

Have you checked the heater core? Could be plugged... hold a hose with a narrow attachment to the inlet side of the heater core on the firewall and if nothing comes out, there's your problem. Also try replacing the heater hoses at the same time, unless they are in real good shape.

 

[beaglegun]

No heater core problems. From my research, it sounds like a control problem or a blend door problem. Anybody have any experiance with either?

 

[creepinjeepster]

There have been a couple threads on here about the blend door. Believe that would lead you back to possibly having a vacuum problem or electrical depending on the year of your truck.
Accessable under the dash, try and manually turn it. If you can and you get heat, it will confirm it's your blend door.

 

[modelageek]

I WISH EVERYONE MADE A SIGNATURE LIKE MINE IT MAKES IT SO MUCH EASIER FOR US TO HELP THE POSTER beagle, there are a lot of posts and threads about heat around here. you need to check the heater hoses to see if they get hot and your upper rad hose to see if that gets hot. If you have a/c you should have a heater control valve probably in line with the heater hose. is your temp gauge working if so what does it say. DID YOU CHECK YOUR COOLANT LEVEL HAS IT RUN LOW. what engine do you have? first thing you have to figure out is if your engine is getting warmed up properly. did this just start out of the blue?

 

[modelageek]

if you had a nice signature like mine we would know what motor you had, if you had a/c, if you are in a warm or cold climate. etc etc....

 

[Ozwynn]

what sig are you talking about?

 

[Andres629]

what sig are you talking about?

I think he was meaning the info in the sidebar under his username. 'Cause I see no sig whatsoever.

 

[modelageek]

My bad I started on a auto forum a long long time ago and we called info about your car and location a "signature" I meant car info and location does any one know what the proper name for it is

 

[Black'03LevelII]

My bad I started on a auto forum a long long time ago and we called info about your car and location a "signature" I meant car info and location does any one know what the proper name for it is

According to my user control panel it is called a "profile"

 

[modelageek]

Thanks. I wish the OP had a nice "profile" like mine. Then it would make it easier for us to help.

 

[Plum Ranger XLT]

Your thermostat could be stuck in the open position.

 

[beaglegun]

There is a 4 way valve installed in the heater hoses before the hoses go through the firewall. There is a vacuum controlled operator with linkage that opens and closes the valve. It never moves no matter where I turn the temp knob. I would think it should? Everything else run with vacuum seems to be working. I don't feel any vacuum on the hose that goes to the valve. I wire tied the valve in both directions and the air temp didn't change. I couldn't feel a change in temp on either hose when I did this. The bottom hose is hotter then the top but the top is warm.

 

[modelageek]

I dont have a/c on my truck thus i dont have the 4 way valve( heater control valve) I am pretty sure that valve is suppose to shut down the heat when you put on the a/c. I would think vacuum to the valve should change when you switch to a/c Did you try and follow the line to see where it goes. I am a little confused on if the heater hoses are hot. the principal is that if one hose is hot going into the firewall and the other hose coming out of the firewall is not hot your heater core is clogged. Are the hoses on each side of the valve hot

 

[modelageek]

I reread your post and you said you wire tied the valve open and closed. I would think that in the open position coolant should flow thru the hoses. if the valve is open then check to see that the hoses are getting hot. if not the core is probably clogged. if both heater hoses out of the firewall are getting hot the core should be ok.