Yukon Hvac Blowing/temp Issues

[bonehunts]

This will be a bit of a long post but by posting all the symptoms and steps already taken, I'm hoping to get to the bottom of it. This is regarding a 2001 Yukon, SLT 4WD.

 

Only after my truck's been running for an hour or more, the amount of air being forced through any of the cabin outlets diminishes. The fan speed doesn't change, only the amount of air coming out of the vents.

 

I believe we've already replaced the actuator, but the problem still persists. One other thing I noted this weekend: If I've got the fan speed on 4 or 5 and move the thermostat from hot to cold (or vice versa), the temperature "sticks". If I lower the fan speed, the temperature will change to the new setting.

 

I have manual controls (no digital).

 

Any ideas on what this could be? The dealer won't do anything to it unless there's a code displayed. I've even taken it to them when the problem's happening and they can't/won't do anything because there's no code.

 

Any help is greatly appreciated.

[bonehunts]

One other thing I noted since we replaced the compressor this summer: there's a TON of condensate that drains from the unit everytime I park it, no matter whether it's been on heat or AC.

[bonehunts]

Anyone?? This is becoming a major hindrance.

[gmtech4]

Anyone?? This is becoming a major hindrance.

 

 

i think i read that you have a air flow issue,check/replace your cabin air filters to start.

[wgabert]

Ok I think you've got two issues here. I agree with the post above, replace your filters in the heater box. As far as the sticky temp control door give this a try. Remove the temp actuator. there are two screws holding it in there. insert a couple of small washers between the heater box and actuator so as to shim the acuator a bit lower. In my truck the door was being forced upward by the acuator and was causing it to bind. Hope this works for you.

 

warren