Can you help with heating problem on 1985 Mercury Marquis?

cookie g

New Member
When I turn on the heater I get heat but only lasts about 10 min. then it blows COLD air and heat won't work at all? Any ideas about what would cause this?
 

train2023

New Member
Sounds like a faulty thermostat, although it could be something else.
Easy fix--about $5-10
Thermostat is located where the upper hose connects to the block
 
Top