It is on the top of the engine right above the thermostat. If you look where your upper hose fastens to engine it is the thing on the aluminum cover that has wires going to it. I have replaced mine but it still fluxuates back and forth. The water pump is probably your best bet if it keeps acting up. It is easy to change the sensor but do not overtighten. The cover is aluminum and will strip out easily.
The coolant temp sensor screws into the thermostat housing. This is located where the top radiator hose connects to the engine.
Should be at the lower section of the coolant recovery tank
The coolant fan sensor is the same as the sensor that shows the coolant temperature on the dash gauge. It is located on the intake manifold.
The O2 sensor is located on the exhaust system there might be more then one
It is located under the coolant reservoir. You can't just replace the sensor. The whole coolant reservoir must be replace. It's a simply 10 minute job.
The coolant temperature sensor can be found on the front of the engine, near the thermostat. Remove the coolant temperature sensor retaining nut, to replace it.
look for a plug on a coolant pipe that has 1 black and 1 yellow wire that will be the coolant temp. sensor
The 2004 Chevrolet Malibu coolant sensor float is located in the radiator. The coolant sensor float replace the level of coolant to the instrument panel.
It is located under the plastic radiator fill tank They only cost about $7 to $9 for the sensor as I bout one today for a 96 Cavalier 2.2
The coolant level sensor on a 2.4 L is under front of the coolant reservoir towards the engine. It has a 2-wire connector on it.
check/replace the engine coolant level sensor located in the engine coolant overflow reservior (located at the rear of the engine compartment pass. side)
coolant temperature sensor are located where the coolant runs in the block near the thermostat housing normally the connector are on top of the sensor and the sensor itself screws in with a deep socket. The temperature sensor is usaully located where the coolant runs OUT of the engine close to thermostat housing.