Parts for your 2008 Toyota Vitz|yaris-Thermostat

2008 Toyota Vitz/Yaris Thermostat — What it does and when to replace it

The 2008 Toyota Vitz/Yaris absolutely uses a thermostat. Technical sources including Toyota’s repair manual for the XP90 Yaris range (1KR-FE, 2NZ-FE, 1NZ-FE engines) and the Toyota Electronic Parts Catalogue list a wax‑pellet thermostat mounted in the water inlet housing, plus a dedicated gasket/O‑ring. Aftermarket service guides (e.g., Haynes for 2007–2011 Yaris) also cover thermostat testing and replacement, confirming it’s a standard part of the cooling system.

On this model, the thermostat manages coolant flow so the engine warms up quickly and then stays in its sweet spot. It typically begins opening at around 82°C, routing coolant through the radiator once the engine’s up to temp. That keeps fuel economy tidy, stabilises emissions, and makes sure the heater works properly on chilly mornings. Too cold and it’s thirsty and sluggish