Hello ALL!

I'm a new member. Just bought a 1999 Ford Expedition EB edition about 2 months ago, and I have to say, me and my pregnant wife love driving it and very happy about our choice. 3 weeks later, we had a leak on the rear coolant hoses. I brought it back to the dealership where we got the truck from and they fixed it. They cut 2 of the 3 coolant hoses that can be seen on the rear passenger side and patched them with rubber hoses. Now the winter season is about to start and I just noticed that the heater is not working on both front and rear. I've been observing this for a while and and no matter how long we drive it, play with the temp dial (set to 29 or max 32), the air coming out of the vents never gets hot. The AC is fine and cool but the heat is lukewarm and never hot.

1. Front Heater. I've done my research here and elsewhere and based on the info I've seen online, I can only assume that It could be the heater core or blend door problem for the front. But before I start the tedious "Dashboard/Console Removal by Alan T" is there a way to determine/verify that it is indeed the heater core or blend door that's causing the problem before removing the dashboard? For instance, how do I know that it's not the thermostat? I heard the blend door makes a flapping noise when it's broken? Any additional info. or areas I can check to isolate the problem would be helpful.

2. Rear(2nd & 3rd row) Heater. I haven't had any luck with the rear heater. Are there any valve(s) for the rear heater that might have been dialed down or closed when the dealer fixed the hose problem? Where is the rear heater core or system located? Like the front heater problem, is there something I can check to determine the cause.

I'd appreciate any help, instructions, or steps you can provide to pin point the problem(s).


Thanks for all the help.

 

The front & rear are seperate systems so you need to look at what is common to both. On the front it won't be the heater core or blend door as they don't affect the rear. I doubt it's the front heater core or blend door affecting the front. Check the carpeting on the passenger side just below the dash. Usually if it's the core it will be leaking and the carpet will be wet. To replace the heater core or blend door is a major undertaking and a big pain in the A. With the heat on look under the hood and locate the hoses going into the heater core, feel them one should be hot and the other cool. The easiest way to check the blend door and core is to use a dremel and cut a hole in the plastic cover under the dash in front of the heater core. You can then feel the heater core to see if it is getting hot and can check the operation of the blend door. Save the piece you cut out so that you can epoxy it back in place. For the rear unit check the overhead controls and make sure the 2nd seat controls are turned to the hot position. The rear unit is all the way in the back on the drivers side. I suspect your problem is a clogged hose. Under the hood you will see 2 hoses going into the front heater core. Just before the core they each have a t in them to feed the rear unit the clog is most likely between the t and the radiator. Disconnect the lines from the front core and connect a hose to one and backflush the system, keep the pressure low so as not to damage the cores. When I did mine I cut the hoses right after the t and then reconnected them with copper pipe nipples and hose clamps. Good luck

 

Thanks for the reply. I'm starting to think no one cares/interested in helping me here.

I've been trying to figure this out the past week or so, but the weathers been really crap the past couple weeks making it harder/impossible to work on the vehicle. So anyhow, lets talk about the front first. I've been told by few forum users here & other sites, that the 2 hoses that goes in the heater core have to be both hot. So drove the car for about 30mins and checked the hoses. They were both hot meaning the coolant is circulating and heater core is okay/not clogged. I haven't check the carpet on the passenger side for leaks but I don't really smell any coolant/leak. I've also replaced the thermostat. Drove it for about 30mins again, and still the air is not as hot as it should be. I will flush the cooling system this week hoping this will solve the problem. I don't really want to start the dashboard removal until I've tried out every possibility.

AS for checking the heater core or blend door, do you mind sending me a picture as to where exactly I should dremel an opening?

I've included some pictures that I took when I checked the hoses.