Go Back   Jeep Garage - Jeep Forum > Jeep Platform Discussion > Grand Cherokee - WJ > Troubleshooting/Problems

Join Jeep Garage Today
Reply
 
Thread Tools Display Modes
 
  #1  
Old 12-21-2012, 02:04 PM
Member
 
Join Date: Aug 2011
Posts: 18
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 1151
Mobbin is on a distinguished road
01 jeep grand cherokee laredo heater issue

I've been having some issues with my heater not working right, my heater does not get very hot anymore and this all started right after I changed my thermostat because my jeep was overheating. I ended up taking it to a mechanic that was able to increase the heat by a little but with this cold weather it doesn't work very well. The heater core hoses are very hot when running at normal temp and i have full coolant. The heat only gets warm when I have it set to circulating too. I have the basic temp control and not the more fancy version on the other models. My car does not over heat at all anymore but this only started right after I changed the thermostat, any suggestions?
__________________

__________________
Reply With Quote
  #2  
Old 12-21-2012, 06:48 PM
Gus9890's Avatar
Premium Member
My Jeep: 2001 4.0L WJ
 
Join Date: Apr 2011
Location: Amelia Island, FL
Posts: 4,473
Thanks: 38
Thanked 48 Times in 47 Posts
Rep Power: 408141
Gus9890 has a reputation beyond reputeGus9890 has a reputation beyond reputeGus9890 has a reputation beyond reputeGus9890 has a reputation beyond reputeGus9890 has a reputation beyond reputeGus9890 has a reputation beyond reputeGus9890 has a reputation beyond reputeGus9890 has a reputation beyond reputeGus9890 has a reputation beyond reputeGus9890 has a reputation beyond reputeGus9890 has a reputation beyond repute
Re: 01 jeep grand cherokee laredo heater issue

Your blend doors may be shot
__________________

__________________
2001 Silverstone Metallic WJ Limited:
Gen III Clear/Chrome Projector/CCFL Halos/LEDs, 8K HIDs, 8K HID Projector/Halo fogs, Clear/Chrome Tail Lights and 3rd Brake Light with LEDS, Diamond Mesh Upper and Lower Fascia, Spectre CAI, Breather Filter, Cabin Air Filter, Low-Temp Thermostat, Jet Stage 1 Chip, MagnaFlow Exhaust with Resonator Tip, Shorty Antenna, Front/Back De-badged
Reply With Quote
  #3  
Old 12-21-2012, 06:56 PM
Frango100's Avatar
Premium Member

My Jeep: 2004 4.7L WJ
 
Join Date: Dec 2009
Location: Brazil
Posts: 4,970
Thanks: 9
Thanked 93 Times in 88 Posts
Rep Power: 525932
Frango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond repute
Re: 01 jeep grand cherokee laredo heater issue

Quote:
Originally Posted by Gus9890 View Post
Your blend doors may be shot
Being the manual temp control system, there is only one blend door. Could be broken, but would be strange that it broke right after the thermostat change. It could be that an air pocket is preventing a good liquid flow through the heater core. The engine coolant temperature is reading normal?
__________________
Frank

JEEP Grand Cherokee 4.7 Lmtd 2004
HID 8000K in low and fog / Quad Squad member
KYB Gas-a-Just shocks / Pirelli Scorpion ATR 245/65/17 - Transgo reprogramming shiftkit.

VW Beetle 2.0 TSI 2013
My new toy
Reply With Quote
  #4  
Old 12-22-2012, 05:32 PM
Member
 
Join Date: Aug 2011
Posts: 18
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 1151
Mobbin is on a distinguished road
Re: 01 jeep grand cherokee laredo heater issue

Yeah my car temp is fine no problems with that. Could it be possible the thermostat is a fail safe and be stuck open explaining why my car doesn't over heat anymore and my heater not getting hot?
__________________
Reply With Quote
  #5  
Old 12-22-2012, 06:13 PM
Frango100's Avatar
Premium Member

My Jeep: 2004 4.7L WJ
 
Join Date: Dec 2009
Location: Brazil
Posts: 4,970
Thanks: 9
Thanked 93 Times in 88 Posts
Rep Power: 525932
Frango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond repute
Re: 01 jeep grand cherokee laredo heater issue

Probably not. When the thermostat will stay open, the engine coolant temperature will go down, so you should see that on the coolant temperature indicator. Since you say that the car temp is fine, the problem should not be the thermostat.
__________________
Frank

JEEP Grand Cherokee 4.7 Lmtd 2004
HID 8000K in low and fog / Quad Squad member
KYB Gas-a-Just shocks / Pirelli Scorpion ATR 245/65/17 - Transgo reprogramming shiftkit.

VW Beetle 2.0 TSI 2013
My new toy
Reply With Quote
  #6  
Old 12-22-2012, 07:39 PM
Member
 
Join Date: Aug 2011
Posts: 18
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 1151
Mobbin is on a distinguished road
Re: 01 jeep grand cherokee laredo heater issue

Okay so it sounds like its the blend door then. If I'm correct to change the blend door it requires taking my dash apart? And where would be the best place to buy a new blend door for my jeep?
__________________
Reply With Quote
  #7  
Old 12-22-2012, 09:46 PM
Frango100's Avatar
Premium Member

My Jeep: 2004 4.7L WJ
 
Join Date: Dec 2009
Location: Brazil
Posts: 4,970
Thanks: 9
Thanked 93 Times in 88 Posts
Rep Power: 525932
Frango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond repute
Re: 01 jeep grand cherokee laredo heater issue

Since the problem could still be an air pocket in the heater core, i would start with this: put the jeep on a slope nose up and with the engine cold and radiator cap removed. Now start the engine and let it warm up. During the warmup the coolant expands and can/will overflow from the radiator, but check if you see any bubbles coming out. Air wants to go to the highest point and maybe with the nose a bit up the air pocket can move away from where it was stuck. Be carefull NOT to remove the radiator cap with the engine hot, because the system will be under pressure, and hot liquid will come out and cause burns.
If that seems to be ok, you could have a look at the blend door actuator. It is hidden behind the glove box door. Remove the door and you will see the blend door actuator. While moving the temperature selector, watch if you can see the actuator moving. If that seems to be ok, remove the actuator and actuate the door by hand. You could also see then if hot air will come out of the vents.
Eventhough blend doors are VERY common on the automatic zone control system, on the manual system they are not. Maybe a bigger change that the actuator is the problem, but still strange that the system was working ok before the thermostat change.
__________________
Frank

JEEP Grand Cherokee 4.7 Lmtd 2004
HID 8000K in low and fog / Quad Squad member
KYB Gas-a-Just shocks / Pirelli Scorpion ATR 245/65/17 - Transgo reprogramming shiftkit.

VW Beetle 2.0 TSI 2013
My new toy
Reply With Quote
  #8  
Old 12-24-2012, 01:18 AM
Member
 
Join Date: Aug 2011
Posts: 18
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 1151
Mobbin is on a distinguished road
Re: 01 jeep grand cherokee laredo heater issue

Alright I will try that ASAP and see if that works and let you know and thanks for the advice it really helps.
__________________
Reply With Quote
  #9  
Old 12-24-2012, 01:23 AM
Hitchhiking
My Jeep: 2008 6.1L SRT8
 
Join Date: Nov 2011
Location: middleburg fl
Posts: 909
Thanks: 0
Thanked 10 Times in 10 Posts
Rep Power: 0
kennzz05 has a reputation beyond reputekennzz05 has a reputation beyond reputekennzz05 has a reputation beyond reputekennzz05 has a reputation beyond reputekennzz05 has a reputation beyond reputekennzz05 has a reputation beyond reputekennzz05 has a reputation beyond reputekennzz05 has a reputation beyond reputekennzz05 has a reputation beyond reputekennzz05 has a reputation beyond reputekennzz05 has a reputation beyond repute
Re: 01 jeep grand cherokee laredo heater issue

might want to consider backflushing the heatercore as well
how to backflush a heatercore 01 grand cherokee - Bing
__________________
Reply With Quote
  #10  
Old 12-24-2012, 11:32 AM
Member
 
Join Date: Aug 2011
Posts: 18
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 1151
Mobbin is on a distinguished road
Re: 01 jeep grand cherokee laredo heater issue

Yeah I've already back flushed the heater core, I did it with just a hose and I didn't notice anything stuck or blocking the hoses so it didn't help at all.
__________________
Reply With Quote
  #11  
Old 12-24-2012, 11:58 AM
Member
 
Join Date: Dec 2012
Location: Norcross GA
Posts: 12
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 660
JeepTechGA is on a distinguished road
Re: 01 jeep grand cherokee laredo heater issue

Are both heater core lines the same temp?
__________________
Reply With Quote
  #12  
Old 12-24-2012, 12:41 PM
Member
 
Join Date: Aug 2011
Posts: 18
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 1151
Mobbin is on a distinguished road
Re: 01 jeep grand cherokee laredo heater issue

Yes when the car is fully warmed up both lines are very warm, I can only touch them for a few seconds until it gets too hot.
__________________

__________________
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
2005 jeep grand cherokee laredo traction control issue Tx240 Troubleshooting/Problems 1 11-27-2012 06:02 PM
04 Jeep Grand Cherokee Heated Seat Issue 85cj7rebuild Troubleshooting/Problems 11 03-27-2012 12:03 AM

Powered by vBadvanced CMPS v3.2.3

All times are GMT -5. The time now is 05:09 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Copyright 2012 - JeepGarage.Org
The Jeep Grand Cherokee Owners Community