Heater Problem
99ORDURANGO
10-06-2004, 11:33 PM
I have a 1999 Durango. I recently had to replace the water pump. Now the heater is not blowing out hot air. The blower motor seems to be working, I can adjust the speed with the switch. The inlet hose that goes into the firewall is hot, so I would assume that hot water/coolant is running through there into the heater/ac assembly. What could be causing this problem now. Any help would be greatly appreciated.
tommychau
10-07-2004, 08:27 AM
Check the outlet hose to see if it is hot, if not, possible heater core plugged. If hot, check your air baffle door which redirects inlet air flow between your A/C coil and your heater core.
99ORDURANGO
10-07-2004, 09:56 PM
Today when my wife got home I pulled of the inlet hose and pulled of the hose that connects back to the water pump and flushed it out. Some nasty looking stuff came out and then the water ran clear. I hooked everything back up and checked to see if I had heat.............it works, I had heat again. My heater core must have been plugged a little or something. Thanks for your reply.
code3
01-02-2005, 12:49 AM
Today when my wife got home I pulled of the inlet hose and pulled of the hose that connects back to the water pump and flushed it out. Some nasty looking stuff came out and then the water ran clear. I hooked everything back up and checked to see if I had heat.............it works, I had heat again. My heater core must have been plugged a little or something. Thanks for your reply.
I may have the same problem. What exactly do I do and does it take long?
I may have the same problem. What exactly do I do and does it take long?
code3
01-07-2005, 12:42 AM
[QUOTE=tommychau]Check the outlet hose to see if it is hot, if not, possible heater core plugged. If hot, check your air baffle door which redirects inlet air flow between your A/C coil and your heater core.[/QUOTE
What year durango do you have and have you had this problem before?
What year durango do you have and have you had this problem before?
tommychau
01-10-2005, 07:33 PM
I may have the same problem. What exactly do I do and does it take long?
It should not take long, just locate your heater hoses going into the firewall from the engine bay. I do not know which end would be the inlet and which end is the outlet but if your heater core is plugged up, the hose what is the warmest would be the inlet hose.
Turn off the engine, let the coolant cool off some so the pressure will ease off. Then remove the hose and connect a water hose that does not have a screw tip on it onto the outlet side of the heater core. If it does not fit, you may need to get a coupler to connect the water hose and the outlet heater hose together. Slowly turn on the water, little by little, so you won't blow the heater core if too much pressure builds up, if you do not see anything come out the inlet side of the hose, chances you will need the heater core replaced.
Hopefully you will see junk start coming out the inlet side and eventually unplug the core, this is not the best way and the core could still be partially plugged up. But by reversing the flow of fluid in the core, you would be pushing out the junk instead of pushing it in. Once you got the core partially cleaned, connect everything back together and run a radiator flush. You may need to do this a couple of times to try to clean up the heater core as well as the radiator core.
If you still cannot unplug the core, chances are your core is really plugged and will need a replacement. Also keep in mind that if you heater core is plugged up, you may want to inspect your radiator core too to see if it is starting to plug up as these two cores will plug up at the same time. I recommend buying the heater core from the dealership vs other aftermarket places.
So far, most aftermarket places only offer a 1 year warranty. Also, check some of the aftermarket cores to make sure it is 100% metal housing and no plastic parts. Dealership is the best place so far and price is nearly the same except the dealership carries a 3/36 warranty. Also, inspect the core onsite when you buy the core from the dealership. I am glad I checked mine as the first two cores the parts guy took off the shelf was either very rusty or look like it has been used. The 3rd core that came off the shelve looks brand new. The labor to replace the core was the majority of the bill as they have to tear down the steering column and the dash to acces and replace the core. My heater core replacment ran me almost $650 including parts and labor.
Good luck on the outcome of your heater core and possibly radiator core.
It should not take long, just locate your heater hoses going into the firewall from the engine bay. I do not know which end would be the inlet and which end is the outlet but if your heater core is plugged up, the hose what is the warmest would be the inlet hose.
Turn off the engine, let the coolant cool off some so the pressure will ease off. Then remove the hose and connect a water hose that does not have a screw tip on it onto the outlet side of the heater core. If it does not fit, you may need to get a coupler to connect the water hose and the outlet heater hose together. Slowly turn on the water, little by little, so you won't blow the heater core if too much pressure builds up, if you do not see anything come out the inlet side of the hose, chances you will need the heater core replaced.
Hopefully you will see junk start coming out the inlet side and eventually unplug the core, this is not the best way and the core could still be partially plugged up. But by reversing the flow of fluid in the core, you would be pushing out the junk instead of pushing it in. Once you got the core partially cleaned, connect everything back together and run a radiator flush. You may need to do this a couple of times to try to clean up the heater core as well as the radiator core.
If you still cannot unplug the core, chances are your core is really plugged and will need a replacement. Also keep in mind that if you heater core is plugged up, you may want to inspect your radiator core too to see if it is starting to plug up as these two cores will plug up at the same time. I recommend buying the heater core from the dealership vs other aftermarket places.
So far, most aftermarket places only offer a 1 year warranty. Also, check some of the aftermarket cores to make sure it is 100% metal housing and no plastic parts. Dealership is the best place so far and price is nearly the same except the dealership carries a 3/36 warranty. Also, inspect the core onsite when you buy the core from the dealership. I am glad I checked mine as the first two cores the parts guy took off the shelf was either very rusty or look like it has been used. The 3rd core that came off the shelve looks brand new. The labor to replace the core was the majority of the bill as they have to tear down the steering column and the dash to acces and replace the core. My heater core replacment ran me almost $650 including parts and labor.
Good luck on the outcome of your heater core and possibly radiator core.
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