1998 Plymouth Voyager Heater

PAT HUGHES

MEMBER
1998 PLYMOUTH VOYAGER

Heater problem
1998 Plymouth Voyager Front Wheel Drive Automatic 189500 miles

The heater does not work and it's winter in Michigan! I flushed the heater core and it's clear and clean as are the lines. The heater control use to work when I would move it back and forth from hot to cold. Now it only blows cold air. By the way, A/C stopped working 5 years ago. Is this an electrical problem with the control or is there a sensor device I need to replace? I did replace the thermostat 6 years ago could that be the cause of problem?
Thanks for your assistance

Patrick Hughes

3 Replies

MERLIN2021

MECHANIC
17,250 POSTS

Does the blower or fan blow air? If so try looking for the temperature blend door.
Let's say for the sake of arguement, the core is ok, which just because it was blown out, may have worked, then it's possible that the temperature blend door is stuck. The shaft it swings on is metal, and over time they tend to rust and binde up, operated the temp knob while you look for or feel for the actuator that moves that door, some actuators ar vacuum operated, some electrical. Either these motors, called servo motors can go bad or the above mentioned issue! If the shaft is frozen, try a small drill bit at the base of the shaft, drill thru the plastic and spray some white lithium grease in there, if you can move it by hand, so much the better! Work it back and forth till it moves freely!