How to change engine coolant - 1985 Lincoln Town Car

P0119 Cadillac Engine Coolant Temperature Circuit Intermittent
Possible causes - Low engine coolant level
- Faulty Engine Coolant Temperature (ECT) sensor
- Faulty engine coolant thermostat
- Engine Coolant Temperature (ECT) sensor harness is open or shorted
- Engine Coolant Temperature (ECT) sensor electrical circuit poor connection What about the obd code? The Engine Control Module (ECM) detected an erratic signal from the engine Coolant Temperature (ECT) sensor during the system monitor test Symptoms - Engine Light ON (or Service Engine Soon Warning Light) P0119 Cadillac Description The Engine Coolant Temperature (ECT) sensor is used to detect the engine coolant temperature. The sensor modifies a voltage signal from the Engine Control Module (ECM). The modified signal returns to the ECM as the engine coolant temperature input. The sensor uses a thermistor which is sensitive to the change in temperature. The electrical resistance of the thermistor decreases as temperature increases.
P119 or P0119 ?

P119 - Shorted Fuel Injector Problem
or

You should first check your coolant overflow tank to make sure there is the proper amount of coolant in it. You MUST check the coolant level when the engine is cold to get a proper reading of the level of coolant. When you open a car's coolant system to flush it is common to get air bubbles in the engine. As the engine warms up, the coolant expands and the excess goes into the overflow tank. When the engine cools, the coolant contracts and it draws coolant from the overflow tank. So, after a flush, you must check the level of the coolant the next couple of times you drive your car because it will take several expanding and contracting cycles for all of the air bubbles to be forced out of the engine. If the level is the same after checking it a couple of times, then you should open the radiator cap check the level there. It should be at the very top of the radiator. (MAKE SURE THE ENGINE IS COLD OR YOU WILL GET BURNED!!!).

If insuring the engine has the proper level of coolant doesn't correct the low coolant light, the next step would be to replace the sensor. In most engines it is just a screw-in plug with a wire on it that transmits to the low coolant gauge in the dash. Most automotive part stores should be able to look up where it is located. It is like changing a spark plug, but you may loose a little coolant out of the engine when you remove the old one, so check the coolant level after changing it.

Good Luck!

Have you recently changed your engine coolant? Have you checked your engine coolant? If you just changed the coolant you probably have an air lock in the system and it needs bleed out. To do this i would need to know more info about the vehicle. Another possibility you could have a coolant leak, IE the water pump, radiator hose, heater hose leak. with low coolant the radiator can't do its job and cool the engine. You could also have a broken water pump impeller. No impeller no engine coolant flow threw the engine and heater core.

Have you recently changed your engine coolant? Have you checked your engine coolant? If you just changed the coolant you probably have an air lock in the system and it needs bleed out. To do this i would need to know more info about the vehicle. Another possibility you could have a coolant leak, IE the water pump, radiator hose, heater hose leak. with low coolant the radiator can't do its job and cool the engine. You could also have a broken water pump impeller. No impeller no engine coolant flow threw the engine and heater core.

As with all engine codes there is no one solution fits all, here is the info on the code from the diagnostic material.
P0118 - Engine Coolant Temperature Circuit High Input
Possible causes - Low engine coolant level
- Engine Coolant Temperature (ECT) sensor harness is open or shorted
- Engine Coolant Temperature (ECT) sensor electrical circuit poor connection
- Faulty Engine Coolant Temperature (ECT) sensor
- Faulty engine coolant thermostat P0118 Description The Engine Coolant Temperature (ECT) sensor is used to detect the engine coolant temperature. The sensor modifies a voltage signal from the Engine Control Module (ECM). The modified signal returns to the ECM as the engine coolant temperature input. The sensor uses a thermistor which is sensitive to the change in temperature. The electrical resistance of the thermistor decreases as temperature increases.

A variety of sensors provide information to the ECM/PCM regarding engine operating characteristics. These sensors and their functions are described below. Be sure to take note that not every sensor described is used with every engine application. Coolant Temperature (ECT) The Engine Coolant Temperature Sensor (ECT) is a thermister (a resistor which changes value based on temperature) mounted on the engine coolant stream. As the temperature of the engine coolant changes, the resistance of the coolant sensor changes. Low coolant temperature produces a high resistance (100,000 ohms at 40°C/40°F), while high temperature causes low resistance (70 ohms at 130°C/266°F). The ECM/PCM supplies a 5 volt signal to the coolant sensor and measures the voltage that returns. By measuring the voltage change, the ECM/PCM determines the engine coolant temperature. The voltage will be high when the engine is cold and low when the engine is hot. This information is used to control fuel management, IAC, spark timing, EGR, canister purge and other engine operating conditions. A failure in the coolant sensor circuit should either set a Code 14 or 15. These codes indicate a failure in the coolant temperature sensor circuit.
---
It looks like the above, under hood, passenger side, upper engine area, mounted in front side of water outlet (according to Autozone.com).

Did you change you ECT (ENGINE COOLANT TEMPERATURE SCENSOR) ?

I wonder why the overheating caused you to change the engine instead of checking with the cooling system. Some time back my 323i overheated and coolant expansion tank burst open, but that probably due to ignoring the coolant level low light for a couple of days. I replaced the coolant expansion tank, thermostat and few hoses connected with the tank and it worked fine for me.
Try to check you coolant level - may be you should have replaced your water pump and not the engine.

it seems like the radiator of your car needs attention. check for coolant level in it, when its cold. if les add some coolant and then see if the problem persists.
--than there are chances of chocking in the coolant pipes, may be they not reached to engine..  
--Check the chock,, that it is not turned on. 
--May be sum loosing nut in engine.

If your oil is white looking on the dip stick, you will have serious damage inside the engine.