Driving uphill Overheating issues

It is possible the engine is not overheating.

Besides the light flashing occasionally what overheating symptoms do you have? Is it losing coolant? Going into limp mode? Is there a temp sensor reading of 248f or more to indicate overheating (assuming no concurrent water pump codes)?

There are two temp sensors and two thermostats. Both sensors can be separately read.

In post 12 is a pic of their readings using the Car Scanner app.

One you may be overlooking is in the Exhaust Heat Recirculation system as described above. The temp sensor for it drives the indicator light directly and is located in the return hose for the Exhaust Heat Recirc system.

The other temp sensor is on the engine and is likely the one you are scanning. That one is not overheating enough at 214f or even 220f to flash the light. It goes through the ecm first.

The Exhaust Heat Recirc system is designed to help warmup the engine quick and then reduce added heat using its own thermostat based actuator. As the name implies it is part of the exhaust system located under the car.

 

Usually there is that overheating smell that one never forgets after you smoke an engine or get ready to.