Chrysler Repair: Chrysler Sebring 2003 Heat issues, blower motor resistor, heater hoses

Question
I have a 2003 Sebring.  I replaced the blower motor resistor block on it last year.  This year it seems that the I can only get hot air when the car is running at high rpms.  Any help would be appreciated.

Thank You

Hadi

Answer
Hi Hadi,
As explained in my statement of "expertise" I am not equipped with manuals beyond '99 so be aware of that limitation. But let me offer a couple of ideas: one is that there may be air trapped in the heater water line which is impairing its flow. This would most likely happen if you had the coolant drained and refilled recently, otherwise forget this one. The flow though the heater core could also be impaired by crud, and to check for that try touching the two hoses that flow from the engine to the heater via the firewall penetration at the center (between the engine and the firewall). See whether the two hoses feel equally warm after driving for awhile. If not, then that would support this theory. You could back-flush the heater core with a garden hose water supply to clear out any obstruction.
If the hoses feel equally warm, and still you don't get enough heat, how is the temperature gauge on the dash reading, if there is one. If not, then does it seem like the radiator up front is fairly cool and the heater hoses also seem cool (compared to near boiling hot, which they should be). If that were the case then you may have a thermostat which is stuck open or at least opening at too low of a temperature. If you have a gauge on the dash and it doesn't rise much about 1/4 scale then I would suspect the thermostat is your problem.
The last possibility is that the mechanical control of the blend-air door (which is controlled by the heat knob on the dash) has become disconnected so that you don't have control of the cool/hot air mixture which is how the temp of the air to the cabin is regulated. If the knob seems loose or you have no effective control, then the cable connection or actuating arm for the door are suspect.
So while those are several possibilities if you can identify one that is more likely then you should be able to improve the heating ability.
Roland