2001 Suburban W/ Secondary Climate Controls...non-auto

[dougg01]

I replaced the faulty lower air-door actuator that sits at the lower, center of the ductwork under the dash. Now temperates can be varied and span most of the range. It had become all or nothing in either direction.

 

Prior to the change the heat was good and hot (great for clearing frost) quick and now at idle and slow speeds there is no 'hot'. It's lukewarm maybe. At highway speeds its hot. Engine temp is constant throuhgout. It was blowing hot before I changed the actuator. Max heat now feels like a bit under maybe 2/3 up on the dial.

 

Another note is that in colder times you can feel cold air coming in the lower passenger-side kick panel area - not necessarily the kick panel. It is not constant and does not change in conjunction with the controls. It hasn't gotten cold enough here yet to allow checking this.

 

How do I diagnose this since my manual doesn't touch on any of these components.

 

Thank you....