No Heat in Lower Level of Car on 2004 Mitsubishi Lancer Sportback

#1

I’ve had my Lancer for several years and this winter I noticed that there’s a problem with the heat. The heater/heater core itself seems to be fine, but I’ve always got cold air coming in the vents by the floorboards.



If I have the heat on bi-level, it just blows cold air down there while the top level is just fine. The only way to get warm air through the lower vents is to put the heater on recirculate, whether you have it on bi-level or just the lower vents.



I’m have some guesses as to what’s wrong, but I"m not totally sure. If anyone could point me in the right direction and give me an idea of how much it could potentially cost (or if it’s worthwhile), I’d appreciate it.

#2

Nothing at all? : /

#3

Airflow and temperature are controlled by flaps, or “doors” inside the HVAC system. One flap, called the “blend door” controls temperature by sending air through either the heater core or the AC evaporator, or both, depending on the temperature desired.

The other flaps determine which vents get the air, and whether or not the air is recirculated.

There must be something preventing one or more of these doors from moving to the correct position. Some systems are electrically operated, and some work by vacuum. I don’t know which is in your Lancer.