Auto Climate Control Problem

[koda2000]

it's raining today so i can't do too much with my latest project (2000 Mountaineer i bought yesterday) but i was playing with the auto climate controls today and something isn't right. i get heat and A/C, but it just seems to come out of everywhere (vents/panel, floor, defrost) all at the same time and the force of the air coming out seems weak even though the fan is blowing on full, which may be because it's blowing out of everywhere at once. for example, when i press the DEFROST button i hear a small click like a relay is switching on, but nothing changes.

i'm not sure where to start looking. from what i've read it doesn't sound like a blend door problem and it doesn't seem like a vacuum leak problem. is there a "door" or servo that controls the direction of the air flow? has anyone else dealt with a similar issue? any help would be greatly appreciated. Thanks in advance for your help.

 

[koda2000]

further on-line research has possibly pointed me in the right direction (or at least a direction). from what i've read on the Mercury Marauder forum, and assuming the Mountaineer EATC is similar, the problem may be that the EATC module solenoid armature o-rings are worn and not holding vacuum. i have a vacuum test to perform tomorrow and, if it's not too hard to remove the module, i may swap it with the one out of my Explorer and see if that solves the mystery. if it does i can try replacing the o-rings or send the module out for repair.

any comments are welcome...

 

[koda2000]

I ran EATC diagnostics today, all ok. pulled out the module took it apart and performed a vacuum test, held vacuum ok. then i compared the '00 Merc's EATC functions to my '01 Explorer. the function were identical, so i guess it's just the way the system works. i was expecting the defrost function to be more like the way my manual control XLT works, with 100% of the air flow going to the defrost vents, but apparently the EATC system works differently. i've never used defrost in my EB (bought it this past July and don't drive it in the rain much) so i wasn't familiar with how it worked. Mystery solved, i guess.