Does the SWORD have anything to do with that? I was under the impression that the SWORD just controled fan speed. I also have a similar problem on my 88 750 except its the driver's side giving me the headaches. When I start the car, both sides get hot just like they should. But once I start driving the heat soon becomes cold on the drivers side. If I turn the fan speed switch all the way to the off position and turn it back on, I get heat for another 1 minute and then it gets cold again. Passenger side seems fine. All vents switch properly, and if I unplug the plug on the heater plungers it still does the same thing. Has anyone had a similar problem to this, or have any idea how I might fix this without going to the Stealership?