I just bought a 1998 F150 and the previous owner put a heater core in it around 6 months ago. The reason I am posting is because no matter what temperature the heater control panel is set at I get hot air coming through the vents and defroster. I am wondering if the hot/cold control is is bad or if there is something he could have done while putting in the heater core. I am very familiar with GMs but will readily admit I know little about Fords. The reason I question his heater core is he said "it was a pain in the a--" and when I opened the glove box and couldn't close it I saw he had failed to put in two of the screws...

Thanks in advance for any help you might have. Also if there is a way to test the heater control panel that would be great!!

 

The problem is likely in one of 3 areas. Your blend control **** (not likely) Your actuator or your blend door. The blend **** activates the actuator electronically which mechanically opens or closes your blend door. It sounds like your problem is no matter how u turn the blend control **** that the blend door is staying open to the heater core, instead of closing it off when turned to cold (blue). I would first remove the actuator from under the dash, keeping it plugged in, turn your blend control **** (temperature ****) and see if the actuator motor is turning the actuator. If it isn't then your problem is not with the blend door but either the **** but most probably the actuator. Actuators are cheap, around $49. That's what I would do....hope it helps

 

When I replaced my actuator, I had roughly the same problem, although I would get intermittent cold air. The actuator was able to removed from the bottom of the dash with removing a few things, no total dash removal. That is another reason to start easiest and work towards hardest.

 

Thanks for the quick and detailed response. Today I turned the key to the on position (where I am able to turn on the fan, ac, etc.) and was unable to hear the actuator. This leads me to believe that it is either the actuator or the control as you said. I am have tommarow off of work and am heading down to the local Pull a Part to pick up a control and will probaly look into an actuator while I am there since the prices are so good. I will post back this weekend to let you know how it went and thanks again!

 

The motor that controls the plenum door was burnt out as well as the plug, 10 bucks and the air is cold!! Now I have a new problem... go figure.

(please see other post)

 

Hello DANTEHICKS,

im having the same issue no a/c just HEAT, where can i find the plug which was burnt ?

 

Fyrewalker,
Can you give me advise on where to locate the acuator, as i cant seem to locate it, and i need to fix the heat in my truck winter is coming and i need heat for the new born.
any advise would help.

Thanks
Dayalalito@gmail.com

 

The black panel in the center where your floor heat comes out. Pop that off. Above the vent on the right side you can see a white actuator motor. The wires plug right front side of it. You will have to remove the vent to get to the back bolt that holds the motor in. Hope this helps.

 

Yep, PMREED is spot on. It is held on by 3 bolts.

 

Thanks for the reply , im in for a days worth of work, i have the center console on my truck.