Prius Overheating and Slow Warm Up

I also have a Prius, although it's a newer model. I had similar symptoms a while back. Have you checked the thermostat? It could be stuck open, causing the engine to take longer to heat up and eventually overheat. Is your water pump functioning correctly?

Thanks for the tip! I haven't checked the thermostat specifically. How can I tell if it's the thermostat that's the issue and not something else like a faulty water pump or a clogged coolant system? Any easy ways to test it myself?

Well, without proper tools, it's tough to diagnose precisely. If the lower radiator hose stays cool even after the engine warms up a bit, that could indicate a stuck thermostat. But honestly, with those symptoms on a Prius, a defective map thermostat is often the culprit. I ended up taking mine to a workshop to get it sorted. Best to get it checked out properly before things get worse.

Appreciate the advice! Sounds like I'll need to bite the bullet and take it in. I'll mention the thermostat to them and see what they say. I got the car repaired, turns out the thermostat cooling circuit motor was defective, and it cost me about 350€. Thanks again!