Hi, I have a Lincoln 1304 that isn't getting up to full temperature

Hi Danny,I have a 2004 Lincoln LS, 3.0 haven't had that problem so far,have 125.000 miles on it.Here's a video I found on your sensor,a lot of things are put on our engines that are hard to get to,like the spark plugs. Lincoln ls 2001 V6 3 0 temperature sensors YouTube

Make SURE That Cooling System Is FULL
Have Actual Engine Temperature Compared To What Coolant Temperature Sensor Indicates

Check coolant levels to ensure they are full. Check for coolant leaks.

What you describe could be considered normal if you are driving in hot ambient temperatures with full coolants levels. Ensure you are using coolant liquid not water.

If fluid levels are full (rad and overflow bottle) and there are no leaks and the temperature gauge is not show engine it running hot; then the sensor that controls the fan(s) should be replaced.

Check the heater matrix valve firstly for it's valve operation and cable operation. Also check that the heater matrix isn't clogged with hair and gunk. this can dramatically affect how much air can blow through it.Check that the pipes leading in and out of it are hot from the engine. If not, then check your engine for coolant leaks, blockages and running temperature. If your engine isn't getting up to heat, then neither will your heater. This could likely be a thermostat which has failed.

replace your thermostat and check the waterpump. The ac "pulls" heat out of the air in the car thereby making it cooler, at the expense of making your coolant heat up even quicker than normal. Try this to see what's going on.. Open the radiator cap, start the engine and wait until the car gets up to operating temperature. You should be able to see the water circulating through the radiator...if the fan comes on, and the water isn't moving, then replace the thermostat. If it still isn't moving after that, the water pump may be no good. Id bet on the thermostat. They're cheap and need to be replaced every so often. If the water is circulating and the fan never turns on, then you check the fan motor, relay, etc. There is also a temperature sensor located somewhere next to the thermostat. It's rare to have to replace that, but if it's faulty, then the fan won't turn on and thus overheating occurs. I am assuming here that if you drove your car up a hill without the ac on, it will overheat or get hotter than normal...So....go test your circulation first and let me know what you find. Oh yeah, when you do the circulation test, turn your heater in the car on full blast too...does it get hot inside the car?

First I would have said your thermostat is stuck open. But if the engine is overheating and the gauge reads cold the cooling system is probably empty. Or there may be alot of air pockets in the cooling system instead of all liquid coolant.
If the system was full and the water pump failed the heater might not work but the gauge would read hot.

called a thermostat and it is under the dash next to the ac unit evaporator

Sounds like a faulty mode door actuator for the a/c in the dash. There are a series of mode doors that controls air temperature and air flow. They are located in the passenger side of the dash. If the temperature mode door isn't closing all the way then when you could still be getting heated air from the heater core when on A/C. The blowing only out of the defrost is a textbook sign of a bad mode door actuator.

SEEMS LIKE TRANSMISSION FLUID LOW.TRANSMISSION SLIPPING TRYING TO GO IN DRIVE.CHECK TRANSMISSION FLUID LEVEL. IF LOW ADD FLUID UNTIL YOU REACH FULL MARK ON TRANSMISSION DIP STICK. WITH ENGINE RUNNING A IN OPERATING TEMPERATURE.IF FLUID LEVEL OKAY.CHANGE TRANSMISSION FLUID AND FILTER IF YOU HAVE NOT CHANGED IN A LONG WHILE.A DIRTY STOPPED UP FILTER WILL CAUSE TRANSMISSION TO SLIP.CANT PICK UP FLUID.

might be the same thing.. but maybe not

personally, it sounds like your IAT (intake air temp) sensor if your dash is displaying incorrect temperatures

If outside temp is less than 60 your a/c should not operate full time and if outside temp is less than 30 won't work at all