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2019 Lexus IS300 Thermostat

4 items

Upgrade your vehicle's thermostat with A-Premium's high-quality options. Choose reliability and durability for a smoother ride.

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A-Premium APTHE008 Engine Coolant ThermostatA-Premium APTHE008 Engine Coolant Thermostat
A-Premium®Part # APTHE008
A-Premium APTHE008 Engine Coolant Thermostat
4.682 Reviews
$35.99
Low stock: Only 4 left
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2-year warranty
90 days free return
Fits 2016 - 2017 Lexus GS200t, 2018 - 2019 Lexus GS300, 2016 - 2017 Lexus IS200t, 2018 - 2019 Lexus IS300, 2020 - 2022 Lexus IS300, 2023 - 2024 Lexus IS300, 2015 - 2017 Lexus NX200t, 2018 - 2021 Lexus NX300, 2016 - 2017 Lexus RC200t, 2018 - 2019 Lexus RC300, 2020 - 2021 Lexus RC300, 2023 - 2024 Lexus RC300
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: 2019 Lexus IS300
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1005V1CR
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Engine Coolant Thermostat for Lexus IS200t IS300 GS200t GS300 NX200t NX300 82℃
A-Premium®Part # APTHE009
Engine Coolant Thermostat for Lexus IS200t IS300 GS200t GS300 NX200t NX300 82℃
4.682 Reviews
$32.99
Low stock: Only 3 left
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2-year warranty
90 days free return
Fits 2016 - 2017 Lexus GS200t, 2018 - 2019 Lexus GS300, 2016 - 2017 Lexus IS200t, 2018 - 2019 Lexus IS300, 2020 - 2022 Lexus IS300, 2023 - 2024 Lexus IS300, 2015 - 2017 Lexus NX200t, 2018 - 2021 Lexus NX300, 2016 - 2017 Lexus RC200t, 2018 - 2019 Lexus RC300, 2020 - 2022 Lexus RC300, 2023 - 2024 Lexus RC300
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: 2019 Lexus IS300
Item LocatedUnited States
Quantity1
ConditionNew
item #1013DVP2
Note
Start to Open Temperature: 82℃.
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Beck/Arnley 143-0976 Engine Coolant Thermostat Housing Assembly
Beck/ArnleyPart # 143-0976
Beck/Arnley 143-0976 Engine Coolant Thermostat Housing Assembly
51 Reviews
$63.99
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3-year warranty
90 days free return
Fits 2016-2020 Lexus GS350, 2019-2021 Lexus RC300, 2019-2021 Lexus RC350, 2019-2022 Lexus IS300, 2019-2022 Lexus IS350
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: 2019 Lexus IS300
Item LocatedUnited States
Quantity1
Part interchange
143-0976
item #1000XDX9
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Beck/Arnley 143-0971 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0971
Beck/Arnley 143-0971 Engine Coolant Thermostat
51 Reviews
$36.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2015-2017 Lexus NX200t, 2016-2017 Lexus GS200t, 2016-2017 Lexus IS200t, 2016-2017 Lexus RC200t, 2018-2019 Lexus GS300, 2018-2021 Lexus NX300, 2018-2021 Lexus RC300, 2018-2022 Lexus IS300
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: 2019 Lexus IS300
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0971
item #1000XH8W
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What is an engine thermostat?

 While all engines can become too hot, if your thermostat isn't working correctly, your engine's well-being is at serious risk. The engine thermostat, often simply referred to as a thermostat, regulates the engine's operating temperature within an optimal range (typically around 195 to 220 degrees Fahrenheit).

How does a car thermostat work?

As a temperature-sensitive valve within the cooling system, a car thermostat responds to changes in coolant temperature. Understanding how it works by the following breakdown steps:

  • Closed position (cold start)

Initially closed to help the engine warm up quickly.

  • Heating up

The engine generates heat during operation.

  • Opening the thermostat

A temperature-sensitive element (usually wax) causes the thermostat to open gradually.

  • Coolant flow

When open, coolant flows from the engine to the radiator.

  • Maintaining optimal temperature

Adjusts coolant flow to maintain the ideal engine temperature.

  • Temperature regulation

Continuously adjusts to prevent overheating and ensure efficient operation.

Signs of a bad thermostat

  1. Overheating: The engine becomes excessively hot due to a stuck-closed thermostat.
  2. Low or fluctuating temperature: A thermostat stuck open results in a cooler engine, affecting fuel efficiency and heating.
  3. Temperature warning light: Illuminates to indicate engine overheating due to a faulty thermostat.
  4. Poor fuel efficiency: Stuck-open thermostat reduces fuel efficiency as the engine operates less efficiently at lower temperatures.
  5. Inadequate cabin heating: Insufficient cabin heating in cold weather with a thermostat that's stuck open.
  6. Coolant leaks: Gasket or sealing issues can lead to coolant leaks.
  7. Rapid temperature fluctuations: The gauge shows rapid swings between hot and cold.
  8. Engine running hot at idle: Higher engine temperature during idle or in traffic due to restricted coolant flow.
  9. Slow or inconsistent warm-up: Longer-than-normal warm-up times, even in moderate weather.
  10. Inconsistent heater operation: This affects the performance of the vehicle's heater, causing inconsistent or inadequate heating in cold weather.

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Jul 29, 2026