2000 Lincoln LS V8 overheats frequently. I can start it up on a cold morning drive around the block and it overheats. I believe this to be a false reading, as I can turn the heater on high and it immediately goes down to normal and will stay there. If I drive it, with the heater constantly on high, it never overheats. But needless to say, this is a severe pain in the summer. I've had everything replaced (thermostat, water pump, coolant, etc.) and no one can figure out what is happening. Any thoughts?

SOURCE: suspect hydraulic driven main cooling fan not

the fan speed could be one problem...the other problem could be wth the radiatr cores being blocked..check whether the heat on your radiator is even front top to bottom and on all sides...if it is not, clean the radiator and check for the problem

SOURCE: 2000 lincoln ls heater not working...thermostat?

- If temp guage reads normal, the lack of heat may be due to the Heater Control Valve. Located in front of the radiator. Lower passenger side. A real bugger to replace.
- The plastic cap just over the thermostat is key in re-filling the anti freeze and bleeding air.

SOURCE: 2000 Lincoln ls overheating

There is a hose on the side of the coolant resevoir that has a straight blade screwdriver fitting in it. Open the fitting and this will bleed the heads on the LS. Without opening this you will never get the air out of the head, trust me.

SOURCE: My 2000 Lincoln LS V8 is overheating.

Sometimes a vacuum leak can cause the engine to run lean and hot, Have Auto Zone run a free code check on the car to search for a stored trouble codes this may help.

SOURCE: My 2000 lincoln ls heater is still not working

Check the 'heater control valve,' which is attached to the heater hose line under the hood. If it is malfunctioning, it will prevent hot coolant from reaching the heater core, with the result being no heat. This is a $30 part, usually not too tough to get at, although I've never changed one on a Lincoln.