Ok so Moms got no heat and shes OLD. 08 GP GT Last year she had 2 thermastats and 2 flushes and after that still no heat. It only goes halfway bettween the 2nd & 3rd line on the temp gauge which if I remember it should be at the 3rd line. I hear the door moving when I switch it from floor to face, ect. So any ideas? I just checked it and it was luke warmish. Any ideas so I can get her some heat before Chicago winter kicks in. Heater core? Could it be clogged after 2 flushes? Thanks fellers