EATC Problems

[Craigerz]

When I bought the X the heater and AC was jacked. He told me the blend door actuator was bad. That was no big deal. Was actually the blend door. After suffering through both of those jobs, it still wasn't right. Traced down the vacuum leak to ball under the air filter. Tried to bypass it for a quick trip and it worked fine at idle, until about a quarter throttle it would lose vacuum and start acting all wonky. Replaced that and then the compressor went. Now Max AC works and blows cold but not hard. Still working on that issue but thats not the issue at the moment. Heater blows hot as heck also. Defrosters work and floor works. Auto seems to work ok I guess. It gets hot as hell but only slightly cold. The vent is acting funny though, but maybe its different on the EATC.

1. If I turn on the vent, it blows hot air though the middle vents. Not sure if its outside air yet but its hot heated air, not outside air temperature air, actual heated air. Is this just a fresh air vent that always blows through the heater core?

2. I read on here about the diagnostics and ran that. The first time I got codes 25 and 30. Reset went for a drive. Now I have codes 24 and 25. I went through the bottom to replace the blend door, so I can see it moving and hear it moving when it runs the self check.

3. I didn't run the diagnostic test when I replaced the actuator, possible this messed it up or maybe won't calibrate right?

 

[Craigerz]

Just verified that the recirculate Max AC/Defrost (whatever its called) flap opens and closes. The heater core shut off shuts off on Max AC.

 

[Craigerz]

Pulled off the bottom I cut out to replace the blend door and can see the blend door moving during the test

 

[CDW6212R]

I don't know what your problem is, but it sounds similar to my Mercury, which I still haven't worked on much. I haven't driven mine much for many years, but I think mine has a blend door issue.

When it doesn't work right, it's just like you described yours. The heat is very hot, Vent is very warm, and MAX is lukewarm almost. The vacuum switch is supposed to stop coolant flow, but there is still some coolant flow no matter what that heater control valve is set at. That's why the vent may feel very warm, from hot coolant. If you were to remove the heater hoses, the Vent position must feel neutral. So on AC, mine would be heating the air, and cooling it at the same time, thus not cold air.

Once in a while I would hear the blend door move/thump, and then the AC would work properly, all cold settings, or vent. That happened many times over many years, and any time the setting would be to warmer, that would force the blend door to move away from the full cold setting. Then bam, no more AC until the random time the blend door would move fully to cold. I'd start the car and select a warm temp, and then MAX AC, which selects 60/cold. That didn't work really, but once in a while(weeks between), it'd work right(blend door did move to full cold). So mine is the blend door broken I'm sure, or else I have no idea.

Can you check or see in any way that your blend door fully reaches each end of motion? If it can't be verified at full cold, I bet it's not and letting air from the heater core get in.

 

[koda2000]

If your blend door isn't closing, or isn't sealing all the way, you wont get cold A/C or much force out of the center vents. Hot air easily overcomes cold air. When my blend door actuator quit, I first thought my A/C wasn't working, but then I saw the compressor was engaging and as the engine warmed up the air coming out of the center vents got really hot. I manually shut the blend door and my A/C was nice and cold again.

 

[Craigerz]

Is there a way to recalibrate the actuator that I didn't do when putting in the blend door? It only went in one way, but should it have been all the way in one direction open or closed so it knew what position it was in? To me it looks like the blend door is opening and closing fully.

 

[Turdle]

Leaves and debris in the hvac box ( heater core and evaporator housing) clogging flow thru the evaporator? stuff can get in there--


You might remove the blower and check. Heck, the evaporator might just need a good cleaning, kind of like your home ac needs--just a thought.

 

[Craigerz]

Thats been on the to do list for awhile. I've had problems with it not blowing very hard. It blows ice cold, but it just barely blows. Figured that might have something to do with it.. I was reading on here about how to go about that when I ran across the self check for the head unit... which brought me to this goose chase. The only real thing wrong beside its not blowing very hard, is that the vent blows hot air, not outside temperature air, and after doing the self check the system wont clear codes 24 and 25.

 

[koda2000]

Is there a way to recalibrate the actuator that I didn't do when putting in the blend door? It only went in one way, but should it have been all the way in one direction open or closed so it knew what position it was in? To me it looks like the blend door is opening and closing fully.

Excellent question. I've wondered the same thing.

 

[Craigerz]

I left it unplugged overnight. Not really sure what that is going to accomplish. When I get home if it hasn't cleared, I am going to pull it off and run the check to see where it starts and stop, and maybe try to align it from there.

 

[CDW6212R]

Thats been on the to do list for awhile. I've had problems with it not blowing very hard. It blows ice cold, but it just barely blows. Figured that might have something to do with it.. I was reading on here about how to go about that when I ran across the self check for the head unit... which brought me to this goose chase. The only real thing wrong beside its not blowing very hard, is that the vent blows hot air, not outside temperature air, and after doing the self check the system wont clear codes 24 and 25.

That tells you that there is debris in the blower housing at the heater core. My "new" truck wasn't always blowing air, and I bought the blower motor controller. That didn't change anything, and then it stopped blowing at all. I bought a new blower motor, and changed it, plus cleaned out the pine needles I found stacked in there. That helped a lot, the airflow is much better now. I used a shop vacuum, and a small rubber hose that would fit down into the bottom of the heater core area. It took less time to clean it, than to find the little hose.

 

[Craigerz]

You can clean all of that just by removing the blower motor from under the hood?

 

[CDW6212R]

Yes, the motor and fan blade are right next to the heater core, where the air comes in. The hardest part was removing the W/W and coolant reservoir, to get at the blower motor.

 

[Craigerz]

Might try this with the F-150 too. It does the same thing, blows cold but can barely even feel it coming out of the vents. That would be a nice free fix.

 

[J_C]

Don't know the age of your F150 but on newer vehicles (not your '97 X) there might also be a cabin air filter to check

 

[Craigerz]

The F-150 is a 92. Funny thing about the cabin filter is I was wanting to build one for the X, after reading somewhere about someone making one for theirs. I think it was a third gen though.

Well I took the blower motor apart and sadly the inside of the duct work and a/c, and heater core was the cleanest part of the truck. Blew the dust off the blower motor.

I re taped and re checked all of the holes I cut out when I replaced the blend door. The bled door is opening and closing fully. Took out the radio and vents and checked to make sure they were sealing.

Seems to be blowing a little harder now, but that might just be my imagination.

Still wont clear codes 24 and 25. Guess I'm just going to have to learn to live with that.

The fan blows hard and at the blend door the air is strong. The air sucking in through the recirculator is also pulling hard. I just feel like I have a leak somewhere and am loosing pressure.

 

[Turdle]

Could it ( the loss) be going to the rear ac duct in the center console?

 

[Turdle]

There is some good information here

http://www.fixya.com/cars/t2501937-code_24_25_blend_door_actuator_showing

 

[Craigerz]

Thanks. I'll read through it. It does help to shut the rear fan off, but nothing major. Now I might pull out the center console and see if it's leaking where those two connect.

 

[Turdle]

You "should" only need to pull the message center-cubbyhole part. As it is, it is the first part you pull when removing the console. Grab it on either side where it meets the main console body, and pull