Heater not warm: replaced heater control valve. Blend door working. Hoses hot.

[freaksarise]

Hello all.
I have not had heat in my passenger compartment for sometime now. I felt the two hoses (under the hood) going through the firewall into the heater core and back out. The in-hose was warm and the out was not. I replaced the heater control valve and now they both are warm. (the intake hose is warmer).

I cut a hole through what I believe is the plenum (under the dash through the glove box) and I can see the heater core. it does not get hot.

I felt the blend door actuator and I feel the door moving and I also hear the deep sound of it closing when changing temperature from hot to cold. The sound of the air blowing also changes. So I am pretty sure that is ok.

It sounds like the heater core is done BUT here is a wild card. Last week after not having heat for a very long time, it SUDDENLY WORKS. It worked for about 10 minutes. I came out from a store, restarted car and it stopped working again.

Any thoughts?

Thanks
Rich
1994 Ford Explorer/4 wheel drive.

 

[ragajungle]

you may have a blockage. The heater core on these is easy as pie to replace... You can actually pull off an opening and have the entire core out and the new installed in under 10 mins.

In case someone recommends it:

DON'T reverse the hoses... This will just push the blockage somewhere down stream and cause other bigger issues.

 

[2TimingTom]

A new thermostat and coolant is where I'd start.

What does the temp gauge on the dash do?

 

[freaksarise]

Thanks guys. I will look into steps required to replace the heater core. I was thinking it would be very tedious and would include removing many pieces of the dash, etc.

The temp gauge seems to be working fine and the car is not overheating so I figured the thermostat was OK.

 

[ragajungle]

On the ranger/ex/b2 there is a panel you remove behind the lower part of the glove box-cant miss it- and viola heater core

 

[freaksarise]

oh - that must be the one I cut the "window" into. haha. just to note, I do have an explorer though. I will take a look in the next week and see if I can make sense of it. Sounds pretty easy now. Thanks! (I will post my updates, results, and solutions)

Thanks
Rich

 

[freaksarise]

Fyi - never did get the heater working. This is why i never posted an update. Had to give up the puzzle to fix other issues w the vehicle.