Thanks for the info on the HVAC. I found something called the Blend Door Actuator that opens/closes the vents or doors to the different areas of the unit but there seem to be 2 or 3 of them and each one operates different vents/doors in the system. I'll keep digging.A thousand miles a week on a vehicle with 230,000 miles on it? Clackty-clack from engine, most likely coming from under valve cover where sixteen valves are being actuated through lifters that wear. I presume I4 valves are adjusted that way.Good luck finding a kit used to make valve adjustment. Many dealers have never seen one. HVAC recirc step motor may have failed or perhaps the vane is jammed or perhaps door is jammed. Access this component by removing glove compartment door. Prepare yourself for a pita. Brake component have probably been replaced several times with that mileage so anything is possible. Some individuals working on cars know what they are doing and some don't. Check run-out of disc with a dial indicator. Check pads for unusual wear pattern and build up . Check hub to disc surface for corrosion that could affect rotor run-out. Go for it pardner.