The heater in your vehicle produces heat from a heater core. The heater core is a small radiator, located under the dashboard of the vehicle which consists of conductive metal with cooling fins to increase surface area. Hot coolant passing through the heater core gives off heat before returning to the engine cooling circuit. The fan for the vehicle's ventilation system forces air through the heater core to transfer heat from the coolant to the cabin air, which is directed into the vehicle through the vents. If there is a lack of hot coolant running through the heater core or (In some vehicles) the valve which opens to allow coolant to flow into your heater core is stuck. It is crucial, however that you immediately check the level of the antifreeze in your radiator and fill it until it is full. Then monitor it and check for leaks. Running an engine without coolant can lead to expensive or irreversible engine problems like head gasket failure or broken/cracked heads or block.
The thermostat is stuck open. Replace.
It is possible that the thermostat is stuck open but I would not immediately jump to a conclusion and rule that out as the problem.
Joef, yes...I've seen them in this horrific position of being "air-bound", and taken to drilling out the rivet on the t-stat, to be able to avoid the air problem, Park on a hill? but a bit disconcerting when full of coolant, yet NO HEAT- Would have to look at the condition of the coolant to see if "stuck open" is the problem- no one wants to boil a pot of water, toss in the t-stat to see at what temperature it is activated, most just replace it, because they are cheap- Back in Wisconsin, we'd simply take them out and throw them away with our fifty dollar cars-
The heater core control valve that controls the flow of coolant into the heater core could be stuck closed, or the linkage to it is broken, not letting the water in to the heater core. It is a cheap part. Here in Maine, we'd simply find locate the problem and replace the part rather than guessing.
...as Berkeley's Sunday mechanic, found myself "Expert on ALL makes and models", lotsa tow-ins and folks that could not wait 'till tomorrow- Guessing was a part of the program. Stumped by a thermo-time switch on a five cylinder car learned about the importance of correct timing belt replacement. Volvos are easy, Hondas are difficult- "master of ALL makes and models" is a tough gig. Not a professional mechanic anymore, but still have all the special tools- Lucky that machine shop service was available on Sundays.
Ford, 2000. You're right. Fords do cheap out on links! There's a world of better ideas, comin' from ford..doncha know? Haven't had to service a Ford in years. Can remember the fuel pump not working, because someone ticked the bumper parking, thus engaging the "safety mode" which shuts off all high pressure fuel. Reset button was hidden behind the driver's kick panel. Kicked my ass, this problem, with no intuitive repair available.
Toyota came in with a seized up engine. The customer did not know what oil was, let alone change the oil. We added four quarts, back twisted to make sure it still turned, turned the engine on, and voila ran like new again- Toyotas can be trusted.
Would not suprise me a bit if our owner never had a coolant flush, and the existing coolant degraded to a crusty-bouldery mess which glued the t-stat open- Just a Guess, mind you, but do know about troubles thru lack of maintenance~
Haha yeah, I agree -- Ford cheaps out allot. I had a similar fuel pump problem with my Lincoln. Well-intended feature but it causes more problems than it solves. I've seen faulty heater core control valves allot -- specifically on Fords.
I LOVE car Gurus! turns out you are not alone in this crazy world. Now I've got a MINI! for the joy of driving! BMWs are sturdy, well made. MINIs haven't been around (since 2002) of the German made variety to exhibit major problems (though the 'permanently sealed' CVT has been troublesome for those expecting dynaflow performance) have yet to do the 30,000 $700 maintainence, drives perfectly, no compaints. Perhaps the finest car ever made.
Looking for a Used Expedition in your area?CarGurus has 19,657 nationwide Expedition listings starting at $2,450.
Search Ford Expedition Questions
Ford Expedition Experts