joedpl

I'm thinking about running by the hardward store and picking up a pack of assorted o-rings. If it doesn't have the size I need then I'll pass the info along.

rmanf150

I just did this fix, and it worked great. Much thanks to the person who discovered this fix.

also some added info. I could not find the exact o-ring for this, but i was able to make something work. they have a set of 0-rings at autozone in the HELP isle. part # 80020 has 2-3 o-rings that worked i just had to file down the o-ring a little bit and it fit very snug and did the trick.

The set comes with many sizes of o-rings and you never know when those can come in use, so its well worth the 7.99

joedpl

Well I finally took my old unit apart and replaced the 4 o-rings. I didn't know what I was doing but since I was working with a malfunctioning unit, if it didn't work out I wouldn't lose anything.

But it did work out and my old unit is functioning properly again. Instead of autozone I went to lowe's and picked up a 10 pack of o-rings (part #96750) (only used 4) and paid $2.12 including tax. Like above it wasn't the exact replacement o-ring but it was close enough and fit snug. I put a little bulb grease on the o-rings so they wouldn't get held up when I put them back in.

Now I just have to get my a/c leak fixed and I'll be back in business.

Tools required-
4- o-rings (5/16" OD x 3/16" ID x 1/16")
Torx T-20 Screwdriver
Small Phillips (PH-1) Screwdriver
Small Flat-Head (V-1.5)Screwdriver
10mm Deep socket
Bulb grease for o-rings (optional)

Rusty Rod

+1 I just did mine and it is working great. I took photos along the way if anyone needs them. It was very easy to do.

harleydriven

Can u send me the the pics I want to do this to my truck to but I don't want to mess it up

Rusty Rod

I will post them with the instruction on page one when I get home.

harleydriven

Cool thanks

Rusty Rod

I'm not going to waste time rewriting the original instruction because they could not be better written, so I have added images to help those that are on the fence doing this simple job.

I know others have revived their EATCs by swapping in the vacuum solenoid assembly from other Ford products, but I decided to dig a bit deeper. The problem was an o-ring inside one of the EATC solenoids. Total cost to fix the problem- 'Bout 25 cents, and a couple hours of my time.

Replacing the o-rings requires disassembly of the solenoids, but that's really not that hard to do, if one has reasonably good mechanical aptitude. But first, make sure they hold vacuum when not energized. Connect a hose to the center vacuum port (where the black tube was connected) and suck it.
It should hold vacuum. If it doesn't, the following fix probably isn't for you.

Start by removing the housing around the Radio/Climate Control by pulling on the two AC vents. It will come off fairly easy as it is only held by pressure clips. There are four T-20 screws holding the EATC module in place. Once they are removed you will need to wiggle the module out of the hole and past the clips for the housing.



The hose assembly is held in place with two 10mm speed nuts. On mine the top middle port did not have a hose connected but I guess this is normal.



The solenoid assembly comes off the EATC module by unscrewing the two T-20 Torx screws on the back side of the module.



Pivot the rear of the assembly up, and disengage the tabs at the front of
the module. Disconnect the solenoid connector.



Lay the solenoid assembly on it's back, and remove the 10 screws holding the solenoids and plenum strap to the plastic frame. At the wiring end of each solenoid, you'll see two metal tabs folded over, that hold the solenoid coil and armature to the solenoid frame.



Straighten these tabs and then carefully pull out the armature, while watching you don't lose the spring or plunger that are inside. Note the o-ring on the armature. That's what we're after.



Next, slide the coil off the end of the plenum tube, and then pinch the ends of the solenoid frame together to release it from the plenum. Once the solenoid is all apart, fit the armature back into the end of the plenum tube to check that the o-ring has a good snug fit. If it does, clean the inside of
the tube, and reassemble the solenoid. You can replace the o-ring if you like, but if it fits well, there's no need.



Make sure you pay attention to the screw flanges on the solenoid frame. Pinch the end of the frame together to fit it back onto the plenum. The spacer that goes at the plenum end of the solenoid has the inside diameter undercut, and four grooves. The undercut end goes toward the plenum, and
you'll see four ribs at the base of the plenum tube that mate with the four grooves in the spacer.

The armature slides back on next, followed by the plunger, and then the spring. (The flat end of the plunger goes into the hole first, if you missed how it came out.) Use a bit of dielectric grease on the o-ring, (I used Nylog) but do not use any oil or anything on the plunger. Make sure the tip of the
armature where the plunger seals against it, is clean and shiny. Don't get any dielectric grease on the tip of the armature. Clean and dry is what you want here. Slide the armature back into the end of the solenoid, and while pressing everything back together, fold the metal tabs back over.

Repeat this for each of the four solenoids. On mine, the one that was leaking was for the floor vent door (red hose). It was obvious when I got to that one. I experienced the same thing. The seals were hard and the ones that were leaking very loose. The armature came out much easier than the others, and when I test-fitted the armature back into the plenum tube,
it was a much looser fit.

You might be tempted to only replace the O-ring on the leaking solenoid, and leave it at that. Don't. (Guilty as charged, yer honor...) Do them all the first time, or you'll be back in there again.

babyballin808

Sticky, Sticky, Sticky!!!
Thats why I love these forums this fix is great, took the truck to the stealership and was told that it was the eatc unit and it would cost $700 for a new unit WTF? Jumped on the forums did a search and found this thread $1.97 later everything works perfectly wich is a plus cause here in vegas we see 110+ temps and its the middle of summer. Much thanks.

joedpl

This would be my first sticky if it becomes one!!

Harley#356

great thread, but if we stickied all the how-to's we'd have 8 pages of stickies

I'll add it to the how-to index!

wbwills

I cannot thank you enough for the GREAT information. Less than $5 cured my problem with only getting air out of the defrost default setting on my 2003 Crown Vic.

My hat goes off to you

Many Thanks

BOSSHOG

.

HD4595

OK so I just replaced all the O-rings and put it all back together and same problem. Still only blowing cold air out of the defrost and the other buttons are still useless.

What do I try next? I was messing around with my boost gauge the day before it happened. Would you think there could still be a control unit issue or is this most likely a vac leak which is why I am only pulling Vac on the gauge and no boost?

Thanks in advance,

joedpl

What kind of o-rings did you get?