Q: no heat on 2001 Mercury Sable

Rookie cbe0621eac06868b3efe0d8d1d3611e23c60d3114864ea2ec19a68cfbd3eebab
my heater just blows cold air ive flushed heater hoses,changed thermastst and my water pump.i just need to know if there is a way i can cut a hole in the plastic peace behind the glovebox to replace my blend door vent?becacause thats my problem
(1) Answer
are you sure?? the heater core is a common failure. did you take the temp of both hoses?? one should be around 140 and the other should be around 120. if that is the case then yes, it may be a blend door issue.
before cutiing any holes, there is a motor that failes often that needs to be checked and is external. make sure it is functioning.
if the door is bad, the entire case must be removed as even if you cut a hole, the door is such a size that it will not come out of the case or under the dash.
take one step at a time.