2008 Audi R8: Ain't That Hot

My 02 Camry's thermometer does the exact same thing, though I don't recall it ever hitting 118. If I left the car sitting all afternoon on a 90 degree day, the car might read 110 when I first got it.

the engine heat was my guess too, until I realized the engine in this car is in the back.

My Subaru does this too if I park the car after the engine is nice and hot and let it sit for a while. I've gotten into the 110+ range many times on otherwise non-scorching days.

I think it's a combination of the stagnant air in your engine bay getting ever hotter by the engine and all the heat radiating up from the asphalt underneath you that's been soaking up the rays.

The outside temp sensor is often in the rear of the car, located low, but nowhere near the exhaust or other hot components. The high temp readings you guys are seeing after parking your cars is probably from heat reflected off the pavement/asphalt baking the bottom of your car. When you drive off the airflow rids the heat soak and the sensor is able to read true air temp.

I think the new gen camry finally solved this problem. My temp is always displayed exactly as the one at the bank, stores, and elsewhere. If anything, its sometimes just one degree above. Pretty accurate in my book!