I have a 90 420sel with a strange heater problem. I have had the blower motor replaced about a year ago. I have started having a problem of the heater seems to work when it wants to. I may start the car up and the heater will not work and only blow cold air. Then, I may push the off and on buttons a few times and it may start blowing hot. Then, if I reach up and move the temperature dial any, it usually causes the heat to get cool again. Sometimes I can turn the car off and then start it again and the heater will work fine for a little while. Does this sound like the push button control is going out? I email Larry Bible, who happens to be a big help on this board and he thought it might be the temperature sensor or the blower sampler motor. What are your thoughts on this? Has anyone ever had this problem before? (I am sure I am not the first). Any ideas of where to start? Thanks.
Scott