Originally Posted by dstones
I'm having the same issue with my 1995 Marquis. Did you get to replace the heater control valve? And if so, did it work out for you?
I'm hoping its not the unit on the dash side, the manual is calling it a heater and AC control assembly..
If the control unit goes bad it will only blow in defrost mode. That is just $.40 of o-rings and easy to fix.