My mama is having trouble with the heater in her 1991 Crown victoria. The engine heats up to operating temperature but very little warm air comes out of the heater. The coolant has been checked and refilled. The thermostat is working properly. Where is the switch that changes of from heating to cooling inside the system? Husband thinks that little switch may not be opening properly and not letting enough water into the heater core but we can't find where the switch is. do any of you know?

Mama's husband passed away last week and she has been sick also. Any info would be greatly appreciated because we hate for her to take it to a garage because the last time she had a simple thing repaired she was charged close to $1000!!! thanks!

-- Suzy in Bama (slgt@yahoo.com), January 19, 2002

Answers

There might be a in line thermostat in the supply hoses that run from engine to heater core, thats how my 87 e150 is set up.

-- mitch hearn (moopups@citlink.net), January 19, 2002.

Does it have climate control or standard heater controls?

When the controls are set on heater and blower motor is on is the air blowing on the floor? Or where?

-- Mark in N.C. Fla. (deadgoatman@webtv.net), January 19, 2002.

does it have AUTO TEMP CONTROL? those controls are known to go out ,, have to replace the whole panel,,does the fan work? that may be another thing

-- Stan (sopal@net-port.com), January 19, 2002.

If there is very little heat but lots of air, then it is water control valve on heater hose in engine compartment, or the temperature selector switch on the dash. If there is very little air at all, then it is a vacuum supply problem, either a hose is unhooked or the blend door actuator is bad, which is located under the dash. Worst case scenario, the heater core could be plugged if no heat. Hope this helps!

-- Gina NM (inhock@pvtnetworks.net), January 19, 2002.

Remove glove box. Remove clear vacuum line from can right in front of left side of glove box. See if you get hot air out of the bottom. Explanation: that can is an actuater for your temperature door. If the temp. control sensor is bad it will have vacuum to the actuater all the time and you'll never get hot air. By pulling the vacuum line you remove the vacuum source. You can plug the vacuum line and have heat all winter. This is generally what the problem is on these things. Answered by my adorable auto mechanic husband - does this help?

-- Katie (homesteader@accessnevada.com), January 19, 2002.

Post your question at carta lk.

If the fan is working, you may have a cable operated valve in the hose that runs from the engine block to the heater box on the firewall that's not activating for some reason.

-- Darren (df1@infi.net), January 19, 2002.

Is the blower motor working?

-- clove (clovis97@yahoo.com), January 20, 2002.