My 2001 lincoln ls is overheating mainly when i turn the a/c on, yes the fan is running an little of the hydraulic was gone, do i need to replace the coolant temp sensor if so laction of it

The LS has a hydraulic cooling fan up until the 2003 model year. I had a heck of a time trying to find the overheating problem on my 2001 LS V-8. The degas bottles are known to split and leak . I replaced mine as it had several splits in it. That didn't help at all. The problem that causes the over heating most of the time is the hydraulic actuator solenoid that is on the hydraulic cooling fan pump on the passenger side of the engine. If you have the car running with the hood open and the a/c on hi cool, the cooling fan should be spinning very fast! The fan should make a pretty loud noise. Mine would spin but not at the high speed it should. If the actuator is not kicking on and opening the valve that allows the hydraulic fluid to spin the fan at full speed then your engine will get hot.
You can find the actuator online for under a $100. To find where it's located get under the passenger side of the car. Find the pump which is on the front of the engine. The actuator is on the side of the pump and hard to get to and see but take your time and use a good light.. Look for a wire that powers the actuator and it will lead you to it. It is a tight job to replace it but it should take no longer than an hour.

There is no relay on the cooling fan circuit.
If the cooling fan is not operating, check fuse #105 (20 AMP), in the underhood junction box, right front of engine compartment.
If fuse is good then test to make sure fan is getting power.
If no power then could be bad cylinder head temperature sensor, hydraulic fan solenoid, a/c cycle switch or the PCM.
If it has power but doesn't come on then fan motor is bad.

the fan will turn on when the engine temp reaches a set temperature and will only turn off when the engine drops below a certain temp and on the highway running hard it may stay on longer

Hi there:Are you check coolant level? Also, there some TSB about some vehicles Lincoln LS 2001-2002 may exhibit an engine overheating condition and/or the Malfunction Indicator Lamp (MIL) may also be illuminated with codes P1285 and P1299 stored in memory. This may be caused by an inoperative Hydraulic Cooling Fan (HCF). Ask your dealer about TSB Article No. 01-21-11 / 10/29/01.
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do u hav the rite thermostat or is it in correct--shud be closed at startup-if not takes long time to get at operating temp and bad gas milage too

Yes we had a Saturn which we thought was running hot and the gauge was always in the centre or over but we had the fan checked and it was working. Our thermostat might of been faulty but we never had a overheating issue..My Mechanic said that we should get a coolant flush that might help.

is your fluid for the hydraulic fan filled left side by the throttal body. have your car idle to it gets hot and see if the fan is spinning if not you might need your fan replaced cause that help for when at idel

Does the system pressurize? Check the radiator cap... something as simple as a bad cap can create all kinds of problems. If the system is pressurizing, I would suggest replacing the thermostat again. If it is not installed properly or is defective (this happens more often than it should) it will leave you perplexed until you replace it again. I hope this helps!

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

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.