I just purchased a 1989 260 E with 76,000 miles.

The car is in wonderful condition, but there is something wrong with the climate control.

First of all, the air conditining does not blow cold at all. I am not, however, convinced that I have a compressor/ condensor/ leak problem. The reason why is that heat blows out of the dash vents and defogger vents CONSTANTLY---even when I press the "O" button to shut the climate control off entirely.

The only way I can avoid being blasted by hot air is to close the dash vents manually and press the button below "Auto" for low fan speed.

Where do I start? Should I check for vacuum leaks? Sould I try installing a new pushbutton control unit?

Help!! It is hot around here!

Thanks in advance for your help!

Ed