climate control problem

[90SVO]

Hey all,

Anyone seen this problem before? I have a 2003 Eddie Bauer. Wife was driving it and said that the fan for blowing air out of the dash, defrost, etc, was turning off and on. I took it for a test run, and the fan is staying on, however, it is constantly changing where the air blows out. For instance, it will start with the AC blowing strong from the vents at the passengers, then all of a sudden they will shut down and the defrost vents will blow strong. This keeps switching back and forth randomly as you drive down the road. Even if the climate control is turned off, and the AC is on and set to the passenger vents only, it will keep switching back and forth to the defrost. Any help appreciated.

 

[90SVO]

Surprising that nobody else has seen this...guess I am just lucky!

 

[cjones101812]

normally defrost is default for no vacuum. check the engine vacuum at the Defrost door, check connections and hoses.

does it go to DEF when accelerating?? or anytime?? bouncing??

 

[81luv]

dash air

I have the same problem exactly,

under acceleration the dash air quits and reverts to defrost. I have vacuum coming from engine at idle, and a lot of times it will not go to dash air unless I turn on max a/c. I know the is a vacuum problem, but where????

I just need to know when to look,

 

[cjones101812]

I have the same problem exactly,

under acceleration the dash air quits and reverts to defrost. I have vacuum coming from engine at idle, and a lot of times it will not go to dash air unless I turn on max a/c. I know the is a vacuum problem, but where????

I just need to know when to look,

generally, the line goes through the firewall on the passanger side near the top. it could also be a check valve under the dash for the AC system. follow the AC system vacuum lines to it.

 

[81luv]

dash air

I found the white line in the enine compartment coming from the firewall under the blower was hooked to nothing. plugging it stopped the problem, but where is it suppost to go??