The water temperature sending unit is on the front of the engine. It is next to the top water hose inlet connection.
have no idea
No there is not a water jacket in an intake manifold they are around the cylinder walls in the engine block.
It should last at least 100,000 miles or more but there is no guarantee.
On the 2001 Toyota Celica, the water pump is located to the right of the radiator. A hose connects the radiator to the water pump.
Try replacing the thermostat.
An engine scanner will give you exact water temperature and gauging by it you can tell.
It should be located in the water outlet.
It is located on the bottom of the radiator
On a 1998 Toyota Tacoma with a 2.7-liter engine, the thermostat is located at the engine's front, near the water pump. To access it, you'll need to remove the upper radiator hose, which connects to the thermostat housing. Once the housing is unbolted, you can replace the thermostat. Make sure to drain some coolant before starting the replacement to avoid spills.
The water pump is run off the timing belt. did you have the belt installed by a Toyota certified technician? if not i would definitely check the water pump seals.
how to replace water pump celica 1987
located on left side of water pump