Some time it works then it doesn't No Heat?

[Gary prososki]

2001 ford explorer sport 4.0 Litre s.o.h.c. Had same problem last month. Noticed the temp. gauge wasn't hot enough I replaced the thermostat. Now temp. is O.K. But the heater works most of time, then sometimes it doesn't work at all. Very Cold. No response from heater temp control blend controls. temp control doesn't respond at all. Radiator is full ,and heater hoses are warm. When it work's fine, it get's Plenty of heat .When no heat, it's really cold air from vents. noticed the A/C clutch is cycling when the heat is on??? Thought the A/C should run when A/C is selected, or when Defrost is selected.?? Not when the heat is selected??? Need some Help. Also should there be vacuum going to the heater hose control valve when heat is selected.???

 

[koda2000]

the A/C will run in any position (to eliminate moister) in any setting but VENT and maybe FLOOR (i don't recall). could be a blend door, blend door motor or (if so equipped) the heater control valve problem. have you checked to make sure the radiator is full? don't go by the overflow reservoir level because if the hose is clogged or cracked the rad will not pull coolant from the overflow reservouir.

 

[Gary prososki]

The radiator is full when cold all the way to the cap

 

[1992fordgreen]

Could be the blend door actuator or the plenum housing that the actuator fits in. To a quick search on that and it will reveal many scenarios.

 

[sloop]

the air is coming from the correct outlet - but the air is not heated?

heated sometimes?

thermostat

sticking - easy to replace

 

[koda2000]

after having changed your thermostat, you indicate that the engine is heating up okay now. where is the temp gauge needle once fully warmed up? it should be very close to the center of the gauge's sweep. as long as it is, your thermostat is working properly. there are 2 smaller hoses that lead into the heater plenum an the heater core. do they both get hot? if they are both hot then your problem is blend door, or blend door actuator/motor related. do you know if your vehicle is equipped with a heater control valve? i think by 2001 Ford did away with the valve, but if yours still has a valve it may be not working properly, which would not allow the heated water into the heater core. the valve (if so equipped) is attached to the heater hoses near the firewall and is vacuum operated.

 

[masospaghetti]

the A/C will run in any position (to eliminate moister) in any setting but VENT and maybe FLOOR (i don't recall).

This. In VENT or FLOOR the a/c will not run, in all other positions the compressor will cycle.

It sounds like your blend door isn't working, either your actuator is bad, or the door itself is broken. The door commonly breaks at the axle and becomes loose, moving on its own and unresponsive to controls. I thought the post 98 models had a better door installed that was sturdier but it sure sounds like your problem.

 

[Gary prososki]

I'll check the blend door tomorrow and see if that's the problem . Thank's for the input. I still think the A/C compressor should be off when the heater is on. not both running. A waste of power and gas mileage. I have a chevy monte carlo and the A/c never runs when I select heat. runs with a/c selected and Defrost to get rid of humidity on windshield.

 

[koda2000]

I'll check the blend door tomorrow and see if that's the problem . Thank's for the input. I still think the A/C compressor should be off when the heater is on. not both running. A waste of power and gas mileage. I have a chevy monte carlo and the A/c never runs when I select heat. runs with a/c selected and Defrost to get rid of humidity on windshield.

well, that's just the way it works. read your owner's manual. if you don't want the compressor to run your choices are to select VENT or FLOOR or you could unplug the compressor for winter, but that wouldn't be very convenient for when you need serious defroster action. plus it's not good to let the compressor sit for months w/out running it.

 

[Gary prososki]

At this time I don't have a owners manual. Just a lame 1991 to 2001 Haynes manual very basic. I guess I will re up to All Data.com for another year. Thier info is very good. I took apart the dash heat and a/c control panel, and learned a few things yesterday. I checked the blend control rheostat I.E. temp selector.It has a 3 wires like most rheostats. The center wire yellow with green stripe is the wiper, left wire red with green stripe, right wire red with white stripe. Read it with my multi meter got 300 ohms to 4.6k ohms both ends. Then went to to blend motor and read back to blend control ,all wires o.k.. Then tried to figure out how to remove blend motor. I bet that's complicated. as I Couldn't reach the 2 screws at the rear of motor. Anyway got lucky when I loosened the 2 front screws the blend motor started to work. Evidently it was In a slight bind. A Pending Problem. But for now, I left the 2 front screws slightly loose and it's working. Also figured out how the heater hose, water valve vacuum works. When the a/c selector is set to recirc. inside air, the vacuum goes to heater valve and it closes it. along with opening the recirc door at the passenger side floor area . Still have a question about blend motor replace or probably blend door .Is there anyway to replace without removing complete dash.??? Like I said I have a pending problem.( Thank's all for the Input to this problem. )

 

[koda2000]

FYI: i have a full set of '01 owner's manuals, in like new condition, with case. if you're interested, PM me.

 

[rollinstone]

I think there's a "How to..." sticky regarding blend door replacement without removing the dash. I did it 4-5 years ago. Took a Dremel cutting disk to the underside of the plenum under the glove compartment and carefully cut out the bottom. When the cutout came out the blend door just dropped to the floor mat. The top of the plastic hinge was toast, the part that sticks into the actuator motor.

Bought a new door kit from Rockauto.com ($15 plus shipping), snapped the new door into the actuator (make sure it snaps in), Gorilla taped the cutout back into place and it's all good.

I recommend Gorilla tape. Used regular silver duct tape and over time the tape adhesive gave way and I had to do 2-3 re-tapings.

 

[Gary prososki]

blend door

Thanks for the input, that sounds like a easy shortcut to a complicated fix.