AC Heater When I turn on the ac heater control at any speed it makes a rumbling noise and does not blow air. I replaced the ac heater blower moter thinking it may be that but it is still making the same noise and not blowing. It also began to smoke out the vents for a few seconds but I turned it off. Any ideas would be appreciated.

There are several possible reasons why your blower, vent, defrost, AC, and heater might stop blowing air:

1. Blower Motor Failure: The blower motor is responsible for blowing the air through the vents. If the blower motor fails, you will not get any airflow from the vents.
2. Blower Motor Resistor Failure: The blower motor resistor controls the speed of the blower motor. If the resistor fails, the blower motor may stop working or only work at one speed.
3. Fuse or Relay Failure: A blown fuse or faulty relay in the blower motor circuit can prevent the blower motor from working.
4. Control Module Failure: The HVAC (heating, ventilation, and air conditioning) control module is responsible for controlling the blower motor and other components. If the control module fails, it can prevent the blower motor from working.
5. Vacuum Leak: If your vehicle uses a vacuum system to control the vents, a vacuum leak can prevent the system from working properly.
6. Broken Blend Door: The blend door controls the direction of the airflow. If the blend door breaks or gets stuck, the air may not flow through the correct vents.
7. Wiring or Connector Issues: Faulty wiring or connectors in the blower motor circuit can prevent the blower motor from working.

Check the fuse or replace the blower.

You don't give much info, so it's hard to give you a good answer. Do you have power up to the heater switch and after turning the heater switch to the on position do you have power to the blower? Did you check the fuses, do you have power on both sides of the fuse? if you do follow that wire and check for power at the other end of it. Some cars have a temperature sensor and the blower will not come on until the temp. is warm enough so that the blower will not blow cold air. If you track the hot lead from the fuse box to the switch, through the switch and to the blower and at any point find you no longer have power, that would be the component I would think is causing your problem. You can also check the blower by running a test lead from the positive side of the battery to the blower motor and see if it runs.

Test the electrical circuits ! Manual HVAC or automatic HVAC ?
Do you know the difference ? Heater / A/C blower motor electrical control diffrent . Manual has resistors an a relay for different speeds , automatic has a blower motor control module .Free wiring diagrams here http://www.bbbind.com/free-tsb Enter vehicle info year , make , model and engine size . Under system click on HVAC ,then under subsystem HVAC controls will pop up . Click the search button , then the blue links . First off you need to know what system yours has , manual or automatic.
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When you turn the heat on,is the blower putting out good wind speed.Do all the vents and defroster have good air flow.Does the A.C. blow with good air speed.

Yes. It could be your motor. If there is voltage or your hear the motor running then it could be a vent door not working. There is also the switch and a blower motor resistor that you can check. Hope this helps.

CHECK BLOWER MOTOR FUSE AND RELAY.IF BOTH GOOD.REMOVE BLOWER MOTOR HOTWIRE IT.IF DONT WORK REPLACE BLOWER MOTOR.IF BLOWER MOTOR WORKS.HEATER AND AC CONTROL SWITCH IS BAD.

You have clean the blower unit , may be its dirty then . and then check the blower resistor unit for malfunction.

not hard to replace blower motor, could have something fell into the vents? check first before replacing motor

Brushes on the motor may be going bad. Blower motor is in engine compartment under wiper motor assembly. The blower motor regulator is under the blower motor. There is an A/C relay behind the fuse box under the screwed down cover.
for lack of motor speed its probably the brushes on the motor or the regulator. If no cold air your charge is probably to low to engage the compressor.