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Author Topic: Jeep Grand Cherokee 4.7L heating problems  (Read 716 times)

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Offline topher91

  • Winch Wench
  • Posts: 24
Jeep Grand Cherokee 4.7L heating problems
« on: December 15, 2010, 02:31:55 PM »
Hey everyone,

I recently purchased a 2000 Jeep Grand Cherokee Ltd.  Everything works extremely well but I have had a couple issues I'm concerned about, especially recently with the cold weather.

1.  Although there are no signs of overheating, there is a smell of coolant coming through the vents.  The heat is blowing warm, and enough to keep the vehicle drivable in cold weather, but not the way it should be.  It should be hot, but it's certainly not.  I deal with it by using the seat warmers + warm air, but I'd like this fixed.

2.  The heat selector switch will allow me to direct heat only to the windshield or front vents, but not to the floor vents.  It has become almost unbearable to sit in the vehicle because the floor is ice-cold.

I'm suspecting heater core, but I can't explain why the selector isn't allowing me to move the hot air properly to the floor.  Any ideas?  Any resident gurus who work from home that can repair this kind of stuff on the cheap? 

Offline i_go_commando

  • UberWheeler
  • Posts: 350
Re: Jeep Grand Cherokee 4.7L heating problems
« Reply #1 on: December 15, 2010, 09:24:22 PM »
not know that particular heater setup, but i have seen heater selectors where something falls down a vent and blocks the flapper from moving its full range. ive aslo seen cables stretch or seize, not allowing full motion..

best bet buy a heater core and the pull it apart
1973 jeep commando -amc 360, 727,203/208, waggy d 44 and amc20- soa, OBA- on hiatus
1958 fc 170 cabover quad cab 3/4 pickup.continetal engine/ 700r4/ dana 300 current project

Offline JackstandJohnny

  • Talks waaay too much!
  • Posts: 4727
  • where Jeeps go to die
Re: Jeep Grand Cherokee 4.7L heating problems
« Reply #2 on: December 15, 2010, 09:27:26 PM »
try a google search of this.
look for 'blend doors' and 'resistor'

the coolant smell is because its leaking into your cab;  the resistorpack is located below the carpet on the passenger side by the kick panel i believe.

go google from here; lotta info about this:  or at least this is a start until someone else pipes up ;)
~ rescue green JKUR on 35s.  typical rubicon build

Offline CatSplat

  • Budget Lift
  • Posts: 183
Re: Jeep Grand Cherokee 4.7L heating problems
« Reply #3 on: December 15, 2010, 09:32:16 PM »
Coolant smell: Usually failing heater core.

Can't select all areas: Blend door failure is very common on Limited WJs, but normally that's a condition where you only get cold air, no heat in one or more zone.

Check out wjjeeps.com for more info about the blend door thing, among lots of other good WJ tech. Start by grabbing any codes from the climate control system, and go from there.

http://www.wjjeeps.com/climate.htm
« Last Edit: December 15, 2010, 09:38:29 PM by CatSplat »
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