If you are condidering a do-it-yourself approach to the cooling system flush, there are kits you can buy at a parts store that install into the heater hoses. You then attach a garden hose to the fitting and flush the system out that way, with the water coming out the radiator cap opening. These work well enough, but I would add a word of caution. Don't apply full household water pressure through the garden hose, just crack the valve a little to get a nice gentle flow going. Too much pressure will blow the seal on the water pump. (Voice of experience here.) You don't want to be doing this in the middle of winter, so in the meantime, crawl under the dash and take a look to see if you can see anything amiss with the blend door actuator, hoses or wires loose, damage where somebody kicked it, or anything like that.
I'm not sure about your model year, but on the 2001, you can at least see the blend door actuator (but you can't remove it) without tearing the entire dash apart. You will probably need to remove the silencer panels under the dashboard.

 

DODGETECH AND IRDANELL its time to step on your guys toes sorry.
The sebring convertable the does not have vac for moving the doors or blend they are all electric motors to start. So that will take out the vac leak issue. Second quote me if I am wrong in your first post u said "I turn off the fan so I don't freeze to death and wait awhile. I turn the fan back on and it is warm again" a broken door does not fix itself just a little its either broken or not.
If u have a fan that is blowing across a heater core and there is little flow oh hot coolant going through it U will get little to no heat. The low fan speed only moves a smallre amount of air and the heater core has more time to transfer what little heat it has.
And as i said the first time U have a clogged heater core or lines. Feel both of the line going into the fire wall if I am wrong u will have both lines be the same temp in and out if I am right U have one colder then the other and the coolant flow is restricted into the heater core and thus U have no heat.

 

CHRYSLER TECH, I think you are right, I think I have a clog. I took it into a semi-truck garage(a friend of mine)(no Chrysler dealer withinan hours drive). He called me later this afternoon and told me I have a major clog. He said the coolant was brown and wouldn't even drain out of the radiator. He said he is going to completely flush the system, radiator and heater core, and install a new thermostat. He said he will also check the water pump. Hopefully this is the only problem and it will be back to new again. He warned me to never mix the green coolant with the newer orange stuff because it makes sludge after awhile. Best part of this is all I have to do is plow the snow from his business one time and we are square!! (His plow truck is layed up)
I will update when I get the car back and thoroughly test it out. Thanks Guys!

 

change out your coolant every 30k I would bet that it has been alont longer then that sence U have done it I see it all to often then u get the brown sludge in there.

 

Okay, It's official!! Heater now works perfect. Can't explain why the car never overheated, the way that sludge looked it should've. I "inhereted" this car with my recent marraige. The car was her mothers before that and I'm not sure how long it's been since a flush was done, but I'm guessing it was the original coolant from new with 101K miles!! Just glad it wasn't the blend door!
Thanks for all your help Guys!!.....Mark

 

Factory recommendation for replacing the gold coolant is 100,000 miles. Maybe somebody put in some green to top it off somewhere along the line. Either that, or don't believe the factory recommendation.

 

99 with a 2.5 is still green coolant most new stuff 00 and up are red

 

I too started having heater issues this winter, my heater only blows warm air so I did a coolant system flush using one of the inline garden hose kits, the water coming out was nasty at first. I was never able to get to the radiator drain so I had to rely on flushing completely through the reservoir and I also removed the upper raditor hose from the water outlet on top of the engine too. Eventually I got the water to come out clear then I refilled the system with a 50/50 blend. In reading the last few posts I'm wondering if I may have put the wrong fluid in, I have a 2001 Sebring with a 2.7L engine and I used green antifreeze. I bought the car used and it didn't have an owners manual. Should I drain/reflush the system and put different coolant in? My heater is still only blowing warm air too. One time since the flush it actually blew hot air but it's just been warm since then. I have no doubt there was some sludge in the heater core given the condition of the water coming out of the system.

Thank you for any helpful replies.

 

!. Be VERY careful when flushing the cooling system that you do NOT apply full city water pressure to the cooling system. The system was designed for approximately 15-16 psi. City water can go up to 90 psi. You run the danger of blowing the seal on the water pump or cracking the radiator or heater core. Just crack the valve on the water tap enough to get a nice steady but relatively slow flow going.
2. The big thing about different colors of antifreeze is that you don't want to mix them. You may be all right with that green stuff, but keep in mind that there are many different metals in the cooling system and the manufacturer of the automobile has tested the system with the recommended antifreeze. Something different might be fine or might not. For peace of mind you might want to stop being the pioneer here and go with what is recommended.
3. You might want to consider flushing only the heater core (by using only the lines running to and from it) to see if that improves its function.

 

dcotter, thanks for the info. I'll do another flush on the system and replace the fluid with the other kind. How do you flush just the heater core? I understand the concept but how do you get the fluid to circulate?

Thanks for all your help!