99 Expedition w/110k miles, electronic air (EATC)... Recently, my hot/cold mix capability failed -- I'd be driving and suddenly the airflow would go 'full hot'. After leaving the car sit for a bit, the hot/cold settings would work for a short while, but then go 'full hot' again, and would stay that way most of the time.

Either one of two things: Blend Door, or Blend Door Actuator. Since there was an excellent thread from lvmilkman available on Blend Door Actuator replacement for the 99 Expy, I tried that first, since it's clearly the cheaper of the two ($57 for the new part, and only about 30 mins effort)... Here is the link to that thread... It also contains detailed instructions on console removal, which is necessary for either repair:

https://www.ford-trucks.com/forums/s...oor+expedition

Unfortunately for me, once I got down there and got the actuator out, I could feel that the plastic input shaft of the blend door was shattered into several pieces (where the actuator shaft fits into the blend door). Crap!! While the blend door itself is only $28, this was a very expensive repair since getting to the plenum chamber where the blend door is located requires complete dashboard removal (dealer quote -- over $1000). In fact, dealer instructed that the plenum chamber needed to come out of the vehicle in order to open it -- requiring removal of the heater core and A/C evaporator (yikes!!! However -- I found that this was NOT necessary). I just couldn't bring myself to pay $1000 for replacement of a $28 part. So, me being an 'average' mechanical skill, I decided to give it a shot myself.

I renewed my subscription to ALLDATADIY, which I've found very useful for service-manual-type details of repairs (that $24 has paid for itself many times over). There was no way I'd attempt the dash removal without a step-by-step guide, with diagrams... After performing lvmilkman's steps above to remove console and replace actuator, I proceeded with the dashboard removal following the excellent and detailed step-by-step instructions I got from ALLDATA.

I was able to replace the blend door in about 11 hours of work on a weekend. It was a straightforward, albeit tedious, job. Below are some points/observations about this job:

I did take some pictures during this process, of the dashboard in it's nearly full disassembed state, as well as a few photos of the plenum that can be seen with the dash pulled back for access. Also, some photos of the broken blend door input shaft that appears to have just kind of 'shattered'. Drop me a note if you want to see these pix.

While it looks pretty scary with everything all taken apart -- the wife came out and nearly pooped a brick when she saw it all disassembled -- if you document your parts and follow the step-by-steps, you shouldn't have any problems. Also -- service manual or ALLDATADIY subscription is absolute must. Only special tools I had to buy beyond normal sockets/wrenches/etc was a complete Torx set, and the torque wrench I mentioned above.

Good luck -- I encourage you to do this yourself if you're moderately comfortable with mechanical things and have a weekend to spare. Was worth $1000 to me!

 

SFC,

Thanks for the encouraging post. It's good to hear stories like this. Always helpful to have folks out there that have done a job like this so others may learn and possibly fall back to them for answers.

If you have any pictures of the proceedure as well as in progress, you may want to add them to a gallery so others may see them.

Thanks again,

Tim

 

I have a 98 expy, had mine replaced in Dec. I could not find a door only from any of my local dealers. I had to order the whole heater box to get the door but the mechanic just pulled the door out of the new heater box and saved me the labor of replacing everything. It still cost me $680.

 

(Sigh.....) I almost hate coming to the Expedition forum, its always bad news. I just finished repairing the blend door on our Ranger and then the Expy starts acting up. I was hoping the repair would be similarly, a quick, fairly straightforward procedure. After reading your excellent post, I gather this will be quite a bit more complicated. Thanks for taking the time to inform the rest of us unfortunate souls - it was much appreciated.

 

The blend door seems to be problem on a lot of ford products. I had a 90 towncar that also had the blend door fail. Seems like 15 years later they are still making the same faulty parts. You would think they could learn, there again this cheap part makes for a very expensive labor repair, more money for ford.

 

Follow up folks...

I've been hit w/several requests for the pictures I mentioned above showing the dash removal and blend door replacement. I went ahead and just created a gallery here at FTE, seven of the key pictures with some comments on each shot highlighting noteworthy points...

Hopefully this helps... Here's the link to the gallery:

https://www.ford-trucks.com/user_gal...&albumid=15041

NOTE: The size and resolution on these is not near what I transmitted, I think FTE converts the photos down to size... If you really want the detail, you'll still need to drop me a note, these were large, clear shots... Hopefully these gallery photos will do for you though

Regards, and good luck
sfc

 

SFC,

Thanks for the great pictures! I may be e-mailing you for the high-res versions just so I can add them to my little bag of tricks.

Thanks again for the info,

Tim

 

Hey thanks for the info, I recently found I need to do this. Could you send the pictures it would make life alot easier. Was it easy to find a new door?
Kevin

 

Ok, guys, thanks so much, you all put me in the right direction. I did have a shop look and they did tell me that it was an "air distribution module". $2000 later, and I will have cold air again. I'm a tightwod, soooo? Here I am.
I like your terms better. Plus, I like that you all said that it could be the motor or the door itself.
Thanks for the help and look for me in the upcoming days.
I'm diving, I need help. If you can send me pictures and info to:
ralphpolanco(AT)hotmail.com

I would really appreciate it.

Thanks again.

 

Thanks for the great info on the Blend Door replacement. I know it has been several months but I was wondering if you still had the pictures, I would like to see them. My husband and I are going to attempt this on our 1998 Expedition and I would like to have any information I can find.

 

...Welcome Utter1459 to Ford Truck Enthusiasts! Please read the Guidelines, it will help you to navigate through and understand this site.

We are happy you have chosen the best source for Fords!

Enjoy FTE....and
JOIN CLUB FTE -SUPPORT THE FORUMS!
…..See you on the boards.

 

Hi --

The pictures are still available in the gallery found on this site, check out the message a few below the original post... There is a link to the photos.

If you need the larger, hi-res images, drop me a note and I'll send them over.

Regards
Scott

 

I have yet to affect these repairs but thought I would post something I found in the meantime. During a recent trip I discovered that if I just slowly and repeatedly "nudge" the temp control **** I can get the blend door to move from cold to hot and vice versa. I can "feel" a resistance through the **** and as long as I did not move the **** past the resistance point, the blend door would move. It takes maybe 2-3 minutes of repetitive nudging to go from one extreme to the other but when I think of how many hours it takes to change out that door, this seems a small price to pay.

 

Its funny that I my wife's Expy has 110k miles and the blend door goes bad on her truck. The sad part is that I just spent $600 in parts replacing the brakes (front/rear), shocks, trans flush, & oil change. The repair shop told me that it was going to run about $1k. I don't have a free weekend (National Guard) so I'm forced to shell out the bucks. Thanks for the info.....great post!

 

Blend door fix: Aeorcolorado posted about 2 posts before this. After reading all the GREAT info posted by all of you, I tried what aero said and it worked for me!!! COLD air coming out right now. Took less than five minutes. Thank you all for the info. Great site and lots of help.

Ron