A lot of people assume that the problem is the heater core. The heater core is difficult to change on the Ford trucks. They have it buried in the plenum box and you have to remove the steering wheel, steering column, dash, evacuate the refrigerant system, drain the radiator, and remove the plenum box to get to the core. Replacing the core is easy, getting to it is a day's work. The Expedition is particularly difficult to get to. It is almost above the transmission tunnel and well buried behind the dash. The Expedition uses the same plenum box as the F150, so any information on that system applies to the Expedition/Navigator.
You need to be sure that the heater core is really the problem before tackling this job. If you have a pool of coolant on the floor, you'll have to go after the core. If the problem is lack of heat, there are some things you need to eliminate before tearing into the truck. You need to make sure that coolant is flowing through the core. Check the temperature of the heater hoses going into the firewall when the engine is cool and see if they warm up together as the engine warms up. If both hoses get hot at about the same rate, this is a good indication that coolant is flowing through the core. You can also remove the hoses and flush the core with a water hose splice from Home Depot and a water hose. Water should flow unobstructed through the core.
If it appears that coolant is flowing and you don't have obvious leaks, the next step is to check the blend door. This door controls the air flow through the heater core and failure is common on Ford trucks. When the door breaks, it can block the flow of air through the core and kill heat and will also have an impact on AC. If the system seems to work intermittently, it's a good indication that the door is broken and rattling around randomly blocking or opening the passage to the core.
For diagnostic information on how to check the operation of the blend door and a cheap easy fix, check the heatertreater listing on Ebay or the web site at heatertreater.net. The dealer fix for the blend door is basically the same procedure for replacing the heater core, so it will be expensive. The HeaterTreater alternative will solve the problem at a fraction of the cost and work and is well within the capability of the average shade tree mechanic.
go to your Hyundai dealer and make it check
How do you replace a heater core in a 1998 Ford Expedition?"
How do you replace a heater core in a 1998 ford expedition?"
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The only fix for a leaking heater core is to replace it.
I just had similar problem with 2000 expedition. It was the bracket not the compressor. but if you don't fix bracket soon compressor will go bad too.
The only fix for a leaking heater core is to replace it.
If the heater is not working in your Eddie Bauer edition Ford Expedition, your heater core is probably junk and needs to be replaced.
It depends on what is wrong. For example. If it is, a thermostat is cheap fix. However, if you need a heater core then prepare to dig dip in your projects. It can be from a few dollars to a few hundred dollars.
To the best of my knowledge, there is no heater or outside air filter on the 1999 Ford Expedition, and Grease Monkey confirmed that when my Expedition (Eddie Bauer version) was in for service.
Where is heater control switch