My 1994 F-150 4X4 302 engine has quit giving HOT air like it used to.
I have replaced the thermostat, flushed the system and added new anti-freeze.
The temperature selector guage is working OK- I have checked the set on it. The damper seems to be working OK.
The guage reads in the normal range and the heater hoses are very hot to the touch.
The core seems OK- the air blowing through it is quite hot. But, the heat seems to "peter out" before it goes very far.
I Need HELP!!!
Morris Holota

 

Are you leaking any fluid anywhere, namely be the right hand side around the glove box. I've never had this problem before, but I have had friends who have had to replace the Heater Core. Not a pretty job.








Evan A.K.A. PastMaster
1993 F-150 302/E40d XLT
1989 F-150 302/Aod 4x4 XLT Lariat

 

I don't know about your specific truck, but Ford used to use a heat control valve that fastened in the heater hose and regulated the hot water flowing through the hose, Like I say though I don't know if they still use them in the newer models.

 

When I had my 88 Bronco, the heater box seal failed. Most of the air (hot or cold) was blown into no mans land under the dash. Pull your glove box out, crank the fan and see if there is any air being blown under the dash.

 

I had the same problem. My truck is a 1980, so I'm not sure how similar it is. Check under the hood, on the heater box, somewhere near where the heater hoses connect. is there a lever that moves when you slide the heater control from cold to hot? The cable that moves the lever had slipped so it wasnt pushing the level far enough towards hot. If it is set up the same, it may very well be your problem. Just undo the clip and slide the cable back to where it should be. Good luck if you havent already fixed your problem... as this is an older thread.

Steve

 

Believe it or not, I took out the heater core to put in a new one. I put my hand in the ducting and found a pen had fallen down the defrost duct to block the door that shuts off the cold air to the heater core.
A cheap fix! But, lots of work before I found this out.
Maybe a message to check out the simplest solutions first.
Anyone ever hear of Achim's razor?
Thanks for the tips guys!

 

Morris,
When you refilled you radiator with antifreeze
and water..,Did you have your heater on? It is a
common mistake to refill radiator without turning
on the heater..,the heater core requires an ample
supply of hot water running through it in order to
provide heat. It sounds like your vehicle has enough water to keep it from overheating but not
enough to provide heat..,refill your vehicle with
the engine and heater running at the same time.
Good Luck,
EBTE tech