I hate to be the bearer of bad news, Paul, but you are about 8 hours away from replacing your recirc vacuum actuators, if you can match MB flat rate times.

The actuators behind the glove box apply to the W126s, and are simple to replace. The actuators on a W124 are right in the center of your dashboard and are impossible to replace without removing the dashboard. Looking at your center vents, picture the actuators very near the windshield and about as far apart from each other as the width of your vents.

When you (or someone else) replaces them, don't stop there -- do all of the actuators. And, though one can purchase the vacuum diaphrams alone to repair them, I wouldn't think of doing that on a W124.

The first thing that I would do if I were you is to ascertain that your evaporator is not leaking. If it is, may as well do it, too, while you're in there -- it's a known problem on these cars and it is about 18 hours labor. Of course, this would subsume the 8 hours for the actuators if an evaporator replacement is needed.

Now, let me tell you about a temporary -- and only temporary -- fix until you replace the actuators. Go to Home Depot or Lowe's and buy some aluminum duct tape (not the cloth type, but the aluminum type) and open your hood. See the air intake for the HVAC? Take about 4 or 5 strips of the tape and completely seal the intake and you now have temporary recirculated air. Repair your car as soon as possible and, while using the tape, make sure that you take in some fresh air periodically in the car by rolling down a window briefly.

Richard Easley
Waco, Texas