Hey Reddit fam!
I have an unusual issue with my 2013 Prius 4. The red engine temp light comes on only when I’m going about 80mph and mostly if I’m going uphill. For example if I’m on the freeway and going uphill almost always it comes on. As soon as the uphill ends it goes away, or if it comes on during flat road at 80mph, if I get off the gas pedal it’ll go off. At idle or low speeds in the city it never comes on. Even on hot days with AC BLASTING, nothing. I got a OBD II Scanner off of Amazon to try and see if I get any codes and I’m not getting anything. No codes at idle and no codes while it actually happens. Anyone with any idea? A mechanic told me that it’s because my catalytic converter is full, but another mechanic told me that it can’t be from that. Car has 430k miles. My next guess is EGR Cooler maybe? Any ideas or suggestions are appreciated. Thank you