Heater won't get hot
Start by warming up the engine, and then shut it off when it is up to operating temperature, and open the hood.
Carefully feel the heater hoses to see if they are hot.
If you are unsure of which they are, ask someone who knows.
They are about 1 inch in diameter and are found at the rear of the engine attached to the firewall.
If they are hot, the problem is likely the flap inside the heater inside the car, which is controlled by a vacuum line or a wire cable.
Someone will need to dismantle the heater box under the dashboard to see about the air flap.
If they are not hot, feel the radiator hoses to see if they are hot.
If the radiator hoses are hot, and the heater hoses are not, you will next check the hot water shut off valve which is in front of the firewall, and in between 2 pieces of one of the heater hoses.
This valve is controlled by a lever on your dash board, that is marked hot or cold, and may have the colors red and blue on it.
Those valves usually fail by "sticking" closed, because lots of people only use the heater a few months of a year.
The valve is opened and closed by a wire cable or a vacuum hose.
If the valve works freely, you may have a "stuck" thermostat in the engine, which would not make enough heat to warm you.
Nowadays, engine thermostats usually stick open when they fail.
A symptom would be the radiator hoses and the radiator are warm but not hot.
Jan 22, 2013 |
1997 Ford Expedition