Heater problems with a 98 Eddie Bauer

[bfukuba]

98 Eddie Bauer, V8 with the Electronic Automatic Temperature Control system(EATC). Mods: KKN filter.
Prob: when I turn the vent on, hot air comes out. Hot air comes out on all settings: vent, pnl, floor, etc unless I turn the temperature all the way down to 60 degrees. So I end up running the air on max all the time. Anyone have any clues? I have a 100k warrenty with the dealer, but if there is an easy fix, I'd just as soon do that then go through the exercise of putting the old filter back on and taking it back to the dealer.
tia

 

[kilroy]

Sounds like the air temperature sensor went bad, it's under the dash somewhere and controls the doors using a bimetal spring and airflow over it is what does the trick. My Grand Marquis had that same problem and I had to replace it twice.

 

[bfukuba]

Hey, that was a quick reply!!
Thanks!

 

[98EBV8]

How many miles on yours when this happened? What is the build date (located on a sticker on the driver's door)?

Thanks,
Shane

 

[bfukuba]

mfg build date is 12/97, and it happened at around the 31K marker.

 

[smithg3]

EATC Blend Door

The problem isn't with the temperature sensor. If the air output from your vents change when you go from 60 deg to 90 deg (panel when 60, and then a crossover to the floor vents some where on the way to 90) then your sensor is working properly. Since the sensor is working properly then it is a part called the blend door. It sits up under the dash to the left of the heater core. It is controlled by an electromechanical actuator (on EATC equipped models, maybe others, not sure)that has a shaft that turns a door in the ductwork. This door "mixes the air between the evaporator case from the A/C and the heater core. Your problem is that the blend door is stuck partially open allowing both heat and cool to enter. When the EATC tries to regulate the temperature by turning the A/C off, the blend door dosn't close enough to limit the heat input. Therefore the temperature cycles between hot and cold with no happy medium. During the summer, my blend door was stuck in the same position yours is in, but know it is stuck in a position that closes the heater core off from the system. Result -- no heat. The blend door part is not cheap, approx $100.00, so If it is under warranty take it to the dealer! This is a common problem due to a bad design and supposedly the problem has been fixed with a replacement part. I did my own, but only with the help of a former Ford tech since mine is out of warranty. Good Luck.

 

[Lubos]

blend door

Where exatly did you say is the blend door? Better to ask where is the heatercore?

 

[smithg3]

I did not buy the part, due to the difficulty of the labor. You have to take the dash out to replace the blend door mechanism. Instead I "jury rigged" the system so it now works 100% now. You may not want to do this if you are not too comfortable, I would suggest taking it to the dealer. If you want to do it, I can post the instructions. BTW, the heater core is behind the glove box, in the black plastic housing.

 

[97sport]

I did mine 2 weeks ago and it took 10hrs. what a poor design, i'm not sure that the new part is any better.(still alot of tension on the door).

 

[Willndtw]

Blend Door Actuator Plentum Broken

Been reading the postings on the A/C Heater issues. I have a 1996 Explorer with about 65K miles. In early 2000, I noticed that it was only blowing hot air. I had it checked out and Ford Service told me it was the blend door actuator plentum that was broken and would cost about $600! I decided not to get it fixed since it was winter time. In the summer, I realized that the Max A/C blew out cool, a/c air, so I used that in the summer. Just a couple days ago, my Max A/C stopped working, and the truck is blowing only hot air (even with the controls set to "off" - hot air is blowing out of my floor and at the windshield). There is a TSB (Technical Service Bulletin) written addressing the issue (#97-24-25), but Ford still will not pay for it. I heard that Ford actually mixed up the doors for the Automatic and the Manual Temp. systems which caused the blend door actuator to fail prematurely. I would think Ford would assist in the repair cost since it sounds like a manufacturing defect. I have written to Ford, and they turned my request down. Has anyone had any experience with this issue and received some assistance? Would love to hear some advice as the repair cost is out of sight, and it's 90 degrees in Michigan right now!! THANKS!!

 

[phfeldmann]

Blend Door Actuator

I have a '98 EB with no heat. Can any provide any suggestions for positioning the blend door so I can get some heat. Anything involving a strategically placed hole, duct tape and a coat hanger would be fine.

I have no intention of forking over ~ $700 - $800 to the dealer to fix one problem and cause 3 - 4 others.

 

[TPLYNCH]

I think it can be reached by removing the glove compartment......

 

[phfeldmann]

Blend Door Actuator

Thanks for post. I think blend door is inside the plenum behind the glove box. From previous posts, it seems like to only way to access is to remove the plenum which can only be done by removing the entire dash board.

 

[97sport]

the part you need to repalce is $150 at a dealer, and your right you have to remove the dash. A haynes repair manual tells you how to do it. plan on 10 hours to do this unless someone helps you. no special tool are needed for the job.

 

[TPLYNCH]

You still may be able to manipulate the blend door without having to open the plenum. I'm not sure tho, since I've never had to do it. There was a thread awhile back where the whole workings of it was discussed.... probably 2 months ago. Search for No Heat or Blend Door or Actuator and you should come across it.

 

[97sport]

I used my dremel tool to cut a hole out of the corner of the pasanger side area to verify it was the blend door.
i could force the door shut and get heat but it would bind up when i tried to open it. if all you want is heat cut a big enough whole to glue the door shut or something and tape up the whole.

 

[phfeldmann]

Thanks for the suggestion. I always wanted an excuse to buy a Dremel tool. Now I have one.

I'll let you know how I make out.

 

[Lubos]

I´ve solved the problem with the heating when I removed the actuator which is behind the glove box. It's attached to the heater core with three screws. One is on the other side of the actuator, bad to reach but it can be done. When I removed it I found out that the bland door was broken on the part where the actuator had to move it. So when I wanted heat I had to open the glove box and move the bland door. Later I found out that the bland door can be moved also when the fan is on and you brake a little harder the bland door moves to the heat position(only when the actuator is removed), know I have done it in a service station.

 

[X24]

I have never looked under there to see what all this stuff looks like but is it at all possible to replace the blend door from there? Even if you got a little creative, it would sure beat removing the whole dash.

 

[97sport]

I thought about it long and hard before i started taking the dash apart. the blend door is put in place and the top and bottom of the assembly are fused together.
I had a big enough hole in the side to replace it but it is a tight fit in there and i could see no way of doing it. but thats just me maybe someone has. the only way i know to get a blend door is to buy the whole assembly.