Hello everyone, I am having a problem with my 323ci. The heat comes out of the vents warm only when the car is in motion. For example when I come to a complete stop and or slow down I get cold air. Whats going on ?
More specifics about the year of your car &/or month manufactured is helpful when it comes to armchair diagnosis. Best I can guess is you have a '99-'00 E46 convertible. I'd guess primary possibilities are a water valve problem (part #2 http://www.realoem.com/bmw/showparts.do?model=BR33&mospid=47705&btnr=64_0890&hg=64&fg=18), or possibly thermostat related. I wouldn't suspect a blower issue offhand. That's assuming you have coolant. When the engine's cold, check your coolant level. Check your fuses, just in case.
My guess would be thermostat. A usual cause of no-heat is because the car isn't warming up like it should. How is your coolant temperature gauge when this is happening? What does it show?
Don't forget to check the outside fresh air diverter (for lack of a better word). Which vents are you referring to? If you are talking about the vents at chest level, there is a diverter in the center cluster. Make sure it is all the way to the warm/red position. If it is in the blue/cold position you are going to get cold air from outside no matter what the HVAC is set at.
