Your temp gage may be malfunctioning
or
you may have a head gasket leak that is making excess pressure build up in the cooling system.
Have the coolant temp sensor tested for accuracy.
This would also prevent the cooling fan from coming on and cause the overheating condition.
Possibly a leak in the coolant reservoir bottle.
If the gauge is reading hot and the car is running normal temperatures, the water temperature sensor needs replaced.
Your oil is hot.
means you are running out of hot water
Bad water pump , problem with engine cooling fan ( if it is actually running hot and not a problem with the gauge or sending unit )
No. Hot or cold. This can be done by running the engine at the same time to ensure the fluid mixes. The danger would be introducing cold water into a hot engine which could crack the block.
If it shows hot on the gauge and it is not hot, there is a gauge or sensor problem.
You probably could A) replace the gauge or B) take it to a dealership and have them look at it
First determine if the engine is really running hot if it is check to see if you are low on water, or could be the thermostat is not opening.The thermostat allows water to enter the engine block after it reaches a certain temp.
That depends on what the car is supposed to run at.
Yes
Check the coolant level, be sure it is to the full mark on the reservoir. Check the temperature gauge, when warmed up it should read aprox 200 degrees F, if not the thermostat may be stuck open, replace it. If the reservoir is full, with the engine running and the temp gauge reads aprox 200 degrees, feel the heater hoses with your hands, they should both be hot. If one is hot and the other is warm or cold, the heater is plugged and needs to be flushed. If both heater hoses are hot I would suspect the temperature blend door is at fault.