Why is the interior heater discharge temperature so hot? It is above 175 degrees.

One possible reason for this could be a faulty engine coolant temperature (ECT) sensor. The ECT sensor tells the engine control module (ECM) the temperature of the engine coolant, which is used to adjust the air/fuel mixture for starting. If the ECT sensor is faulty, it may be sending incorrect temperature readings to the ECM, causing the engine to not start in cold weather.

Another possibility could be a weak fuel pump check valve. When the fuel pump check valve fails, it can cause the fuel pressure to drop when the engine is turned off, which can cause hard starting in cold weather .

It's also possible that the battery is weak and not providing enough power to start the engine in cold weather. Cold temperatures can reduce the battery's cranking power, which can make it difficult to start the engine.

I would recommend taking your vehicle to a certified mechanic to diagnose the issue.

There could be a few different issues that could cause the temperature gauge on your 2008 Ford Focus to read hot when the engine is not actually overheating. Here are a few things to consider:

Failed thermostat: The thermostat is responsible for regulating the flow of coolant through the engine. If the thermostat is stuck in the closed position, it could cause the temperature gauge to read hot even though the engine is not overheating.

Failed temperature sensor: The temperature sensor sends a signal to the temperature gauge to indicate the engine's temperature. If the temperature sensor is faulty, it could cause the temperature gauge to read hot even though the engine is not overheating.

Wiring issue: If there is a problem with the wiring that connects the temperature sensor to the temperature gauge, it could cause the gauge to read hot even though the engine is not overheating.

To determine the cause of the issue, it may be necessary to perform some diagnostic tests and possibly replace some components. A mechanic or a professional auto repair shop will be able to diagnose the problem and recommend the appropriate repairs. It's also a good idea to keep an eye on the engine temperature and take note of any other symptoms or issues you may be experiencing. This information can help the mechanic diagnose the problem more accurately

The engine is swelling because of the over heating. Stop using it !!!!!!!!! Gotta fix cooling system lest you seize the engine.

Low coolant level in engine will result in no coolant reaching interior heat exchanger. Otherwise, check environmental controls. Feel heater hoses under hood to see if they get warm when engine is warm. Could be control valve is not being opened to allow hot coolant into interior heat exchanger.

Thermostat may not be working properly, hot coolant has to circulate via the heater core in order to get heat. Normally operation temperation should be 180 to 200 degrees.

OVERHEATING CAN BE CAUSE BY MANY THINGS LIKE FAULTY THERMOSTAT AND FAULTY RADIATOR PRESSURE CAP,TOO MUCH WATER IN COOLANT SYSTEM NEED 50 / 50 WATER AND ANTIFREEZE.LOOK FOR WATER PUMP WEEP HOLE LEAK, IF COOLANT LEAKING OUT WEEP HOLE WATER PUMP BAD NEED REPLACING.CHECK FOR LOW COOLANT LEVEL, YOUR RADIATOR OVERFLOW JUG SHOULD HAVE COOLANT AT THE FULL COLD MARK IF NOT KEEP ADDING COOLANT INTO COOLANT OVERFLOW JUG UNTIL COOLANT STOP DROPPING AND FULL COLD MARK, IF OVERFLOW COOLANT JUG WAS EMPTY RADIATOR IS LOW ON COOLANT.WHICH CAUSE AIR IN COOLANT SYSTEM KEEPING THE ENGINE COOLANT TEMPERATURE SENSOR FROM BEING SUBMERGE IN HOT COOLANT WHICH TURN ON THE COOLANT FANS.WHEN ENGINE COOLANT TEMPERATURE GET CERTAIN SET TEMPERATURE LIKE 190 DEGREES THE PCM AND COOLANT SENSOR WILL TURN ON COOLANT FANS, IF VECHICLE OVERHEATING COOLANT FANS NOT WORKING EITHER YOU HAVE FAULTY ENGINE COOLANT TEMPERATURE SENSOR CHECK COOLANT FANS FUSE AND RELAYS. YOU CAN CODE SCAN CAR TO SEE IF YOU HAVE FAULTY PCM, FAULTY ENGINE COOLANT TEMPERATURE SENSOR OR FAULTY COOLANT FAN RELAY.IF COOLANT FAN AND ENGINE COOLANT TEMPERATURE SENSOR OKAY,YOU HAVE CORRECT COOLANT LEVEL IN COOLANT SYSTEM, THERMOSTAT AND RADIATOR PRESSURE CAP BEEN REPLACED, YOU COULD HAVE BLOWN HEAD GASKET CHECK ENGINE OIL LOOKS LIKE MILK SHAKE HEAD GASKET BLOWED ALSO WHEN HEAD GASKET BLOWED YOU CAN DRIVE CAR SHORT DISTANCE START OVERHEATING AND YOU LOOSE ENGINE POWER SUSPECT BLOWED HEAD GASKET.

Sounds that you are low on coolant so low that the coolant sensor is no longer immersed in it If the coolant sensor is prevented from working, due to low levels of coolant, then the engine radiator cooling fan will not be started and overheating will result. The gurgling you hear is due to air in the system. When the engine is cold remove the coolant reservoir cap. Set the interior heater to max temperature. Top up the reservoir to the maximum limit with water/antifreeze mix (2:1 is usual). Start the the engine. Be prepared to add more coolant mix as air is cleared from the system. When the top hose from the engine to the radiator gets warm give it plenty of squeezing to help shift any air pockets. The fan should also start at about this time. Make sure that the interior heater is blowing hot air. When the gurgling has stopped and no more coolant needs to be added to stay at the max level then replace the reservoir cap and secure it firmly. Allow the engine to reach running temperature. Check all hoses, junctions, gaskets water pump seal etc for any signs of leaks as it would be good to detect any cause for the previous loss of coolant.

check for coolant level in the radiator
indicates insufficient coolant level

Make sure the reservoir coolant tank is at 'full'. Start the car from cold and observe. After a couple of minutes when the engine has begun to drop in revs ( the coolant temperature sensor should tell the ECU to begin to shorten the injection cycle as the engine warms) the top of the engine and the coolant passage to the thermostat housing should become warm to the touch. When hot the top rubber hose to the radiator should become warm and then hot as coolant begins to circulate. If the top hose fails to get hot at any time then the thermostat is at fault. If you have electrically driven radiator fans these should now come on. If they fail to come an at all you need to check the coolant temperature sensor, the electrical motor fuses and the motor relay. Lastly check the motor itself (just run a 12v supply to it directly). As the ar continues to idle, with the fans running, the bottom return hose from the radiator to engine should also become warm. If the bottom hose fails to become warm this points to circulation problems. Either the radiator had become clogged with rust sludge and needs an extensive flushing out with a high pressure hose or the pump is not functioning as it should. Quickly check that the interior heater works by asking for 'full heat with fan on full'. If the interior heater works this indicates that the main coolant pump is probably OK. To check the thermostat more thoroughly, remove it from the car and drop it in a pan of near boiling water; the 'stat should pop open. As the pan cools, at 88 degree centigrade or so, the 'stat should pop closed. Failure to observe this tells you the 'stat is a dead and needs to be renewed.

check the coolant level in the radiator it may be low
and starving the heater core