I've just recently bought an E36 323i Sports touring. (1999) 136k Miles. No matter how fast the fan is running, there just doesn't seem to be much airflow out of the heater vents, especially the vents below the screen. The fan does change speed with the control, from slow to fast, but just no real change in airflow. I tried pressing the 'recirculate' button to see if that made any difference and it didn't (I was hoping the low airflow was due to a blocked microfilter). Any ideas as to diagnostics procedure on this fault? Thanks for any links or ideas.
JB