Can you help me figure out what is going on?
Recently I noticed that my heat only likes to work when I'm under throttle. Temp gauge shows normal all the time including when I'm warming the car up. When I'm accelerating, the heat works great. Once I coast or stop, the heat slowly goes cold - blower motor continues to work as usual, but the temperature gradually cools off to the point where I have no heat, just cold air.
A couple other things I've noticed:
- My radiator fan has been kicking on after light driving (7 miles) in cool temperatures (20F)
- After normal driving (on occasion) I've heard my coolant boiling over into my over flow tank. It has never spilled over that I'm aware of
- After I shut my car off, I usually (not always) hear a repeated clicking noise from the middle of the dashboard that eventually goes away (after 1-2 mins). It sounds like the CD player is switching CD's continuously, but I have the feeling this might actually be something within the HVAC system that is trying to open/close, or maybe even something else
- Car ('05 LGT) has 140K, stock minus AP
- All maintenance, including coolant and water pump, has been serviced on time
- Replaced the radiator within the last 20K miles
- Pretty sure the thermostat has not been replaced
Can you help me diagnosis this issue? I'd love to stay away from the dealership if I can, but without help, that's exactly where it's going (when they replace my damn airbag that's being recalled).