You have to first start checking if you spark at the plugs and fuel coming to the fuel injectors and electrical pulses to the injectors so that they inject the fuel in the cylinders.

 

The P0117 code indicates that the voltage coming back from the sensor is low, likely due to a short. It is possible that the new sensor is faulty but more likely you have a short somewhere in the wiring between the ECM and the sensor (there are two wires, one supplying power to the sensor and one sending a return signal from the sensor). When the ECM gets no (or faulty) signal from the sensor it doesn't know what temperature the coolant is at and then goes into limp mode to prevent damage to the engine. This would explain your sudden loss of power.

 

The P0117 code indicates that the voltage coming back from the sensor is low, likely due to a short. It is possible that the new sensor is faulty but more likely you have a short somewhere in the wiring between the ECM and the sensor (there are two wires, one supplying power to the sensor and one sending a return signal from the sensor). When the ECM gets no (or faulty) signal from the sensor it doesn't know what temperature the coolant is at and then goes into limp mode to prevent damage to the engine. This would explain your sudden loss of power.

I believe it should still start though?

 

It was the thermostat which was replaced previously, not the actual temp sensor, correct? The car will be difficult to start if the temp sensor is faulty due to what @TeamYoder said (but I think he was under the impression the sensor was replaced, which I don't think it was). There may be a test for the sensor, but I'd have to look it up when I have time (if).

 

While on a break, I was able to look this up. It confirms what @TeamYoder said. My bet is if the wiring to the sensor looks OK, it is probably a failed sensor.

I didn't have enough time to copy the test procedure, but it involves checking for resistance at the connector. If you have a scanner which reads live data, it will tell you what the sensor is telling the computer the temperature is. If it's very high, it's one test. If it's very low, it's another test.

 

My Sienna threw a P0117 code.

Symptoms:
Radiator fan spinning up higher
A/C would run hot at idle
A/C would cool intermittently while driving
Dash gauge for engine temp would go from dead cold to extreme hot
Car would go into limp mode (no start, no acceleration)

Cause:
Low coolant
Air in the radiator (a lot)

What causes the low coolant? Leak or not enough after the thermostat was placed.

For me, one of the stems on the coolant filler tube snapped off. The hose connecting to the stem was flush up against the filler neck, so not visible. I filled the reservoir and radiator with 1 gallon of coolant. Then, it kept leaking off the filler neck. Upon closer inspection, I noticed the snapped stem.

So... it's not always the sensor or the thermostat.

 

I have exactly the same issue with my Camry'09. Was this issue resolved? May I know what was done to resolve this uissue please ?