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confused

Old Oct 10, 2010 | 05:08 PM
  #1  
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Cdy1
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confused

i put a new heater core in an 03 4.6 and it worked the first day very hot and now it doesnt get hot and the ac compresser comes on when i thurn the *** for panel and def.. what do i do??
 
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Old Oct 10, 2010 | 11:07 PM
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Bluegrass 7
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You are discribing two different issues.
First there may still be air locking the heater core circuit preventing flow and heat.
Second, the A/C compressor is supposed to run in the panel/def position.
How well do you think the windshield would clear if the air blown on it were not dried by the A/C system in both a heat or cool adjustment on the panel?
The inside fog is moistue that needs to be evaporated by dry air, for fast clearing.
Good luck..
 
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Old Oct 11, 2010 | 12:12 AM
  #3  
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ottawaguy
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From: Gatineau, Quebec
AS for the heat...I would say it is a flow problem now as well. Was there indeed a problem with the old heater core? Perhaps the system does still have some air in it as previously mentioned or perhaps the system needs a really good flush.

I am not sure about the other issue, so I'll leave that to someone else
 
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Old Oct 11, 2010 | 08:07 PM
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From: Sparta NJ
the only settings that dont use the ac compressor are floor and dash/floor. all other settings use the compressor
 
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Old Oct 11, 2010 | 08:28 PM
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i would check water level as recommended...then consider the blend door inside the heater duct. DId you check it ? Could it have got bent/ stuck ? Above the transmission hump is a motor that controls the door position. That mixes hot and cool air to get the temp you want... and you always want to check the dash **** first to make sure it dont slilp on the shaft. pull the **** off and check.
 
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