Review on TOYOTA 90916 A3003 Genuine Toyota Thermostat by Alex Montgomery

Works like a thermostat. I would recommend always keeping that in mind when purchasing. You don't want to go to great lengths to replace any of them, especially when you have to remove the alternator and serpentine belt like I did, only to find it doesn't work. You test the thermometer in a pot of boiling water, it should be open or fully open at around 85 degrees. Opens slowly, not super fast. Check youtube. Was packaged like a ghetto and I was worried it might be damaged but it worked fine and had an actual sticker. Don't skimp on the cheap and buy third-party vendors. My Vibe has done 200,000 miles and I only did mine as preventive maintenance as I did and flushed the rest of the coolant system.