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Mazda Thermostat

101 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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Engine Coolant Thermostat for 1995-2002 Mazda MilleniaEngine Coolant Thermostat for 1995-2002 Mazda Millenia
A-Premium®Part # APTHE043
Engine Coolant Thermostat for 1995-2002 Mazda Millenia
4.798 Reviews
$24.99
Low stock: Only 3 left
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mazda Millenia: 1995 1996 1997 1998 1999 2000 2001 2002
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mazda
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1012NQ9T
Show less
Engine Coolant Thermostat for 1995-2002 Mazda Millenia
A-Premium®Part # APTHE023
Engine Coolant Thermostat for 1995-2002 Mazda Millenia
4.798 Reviews
$26.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mazda Millenia: 1995 1996 1997 1998 1999 2000 2001 2002
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mazda
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1012NEA9
Show less
Engine Coolant Thermostat for 2012-2014 Mazda 5
A-Premium®Part # APTHA0326
Engine Coolant Thermostat for 2012-2014 Mazda 5
4.798 Reviews
$26.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mazda 5: 2012 2013 2014
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mazda
Item LocatedUnited States
Quantity1
ConditionNew
item #10177DUR
Note
Start to Open Temperature: 90℃.
Show less
Engine Coolant Thermostat Housing Assembly for 2012-2017 Mazda 5
A-Premium®Part # APTHA0082
Engine Coolant Thermostat Housing Assembly for 2012-2017 Mazda 5
4.798 Reviews
$23.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mazda 5: 2012 2013 2014 2015 2016 2017
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mazda
Item LocatedUnited States
ColorBlack
ConditionNew
item #1012Y5CT
Note
Engine Coolant Thermostat Housing Assembly -- Cover, Includes Thermostat.
Show less
Engine Coolant Thermostat for 2012-2018 Mazda 3
A-Premium®Part # APTHE043
Engine Coolant Thermostat for 2012-2018 Mazda 3
4.798 Reviews
$24.99
Low stock: Only 3 left
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mazda 3: 2012 2013 2014 2015 2016 2017 2018
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mazda
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1012NLKU
Show less
Engine Coolant Thermostat for 2012-2018 Mazda 3
A-Premium®Part # APTHE023
Engine Coolant Thermostat for 2012-2018 Mazda 3
4.798 Reviews
$26.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mazda 3: 2012 2013 2014 2015 2016 2017 2018
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mazda
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1012NAZ6
Show less
Engine Coolant Thermostat for 2003-2013 Mazda 6
A-Premium®Part # APTHA0326
Engine Coolant Thermostat for 2003-2013 Mazda 6
4.798 Reviews
$26.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mazda 6: 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mazda
Item LocatedUnited States
Quantity1
ConditionNew
item #10177LRG
Note
Start to Open Temperature: 90℃.
Show less
Engine Coolant Thermostat Housing Assembly for 2003-2013 Mazda 6
A-Premium®Part # APTHA0082
Engine Coolant Thermostat Housing Assembly for 2003-2013 Mazda 6
4.798 Reviews
$23.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mazda 6: 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mazda
Item LocatedUnited States
ColorBlack
ConditionNew
item #1012Y9WN
Note
Engine Coolant Thermostat Housing Assembly -- Cover, Includes Thermostat.
Show less
Engine Coolant Thermostat for 2014-2018 Mazda 6
A-Premium®Part # APTHE043
Engine Coolant Thermostat for 2014-2018 Mazda 6
4.798 Reviews
$24.99
Low stock: Only 3 left
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mazda 6: 2014 2015 2016 2017 2018
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mazda
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1012NPAE
Show less
Engine Coolant Thermostat for 2014-2018 Mazda 6
A-Premium®Part # APTHE023
Engine Coolant Thermostat for 2014-2018 Mazda 6
4.798 Reviews
$26.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mazda 6: 2014 2015 2016 2017 2018
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mazda
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1012NCGQ
Show less
Engine Coolant Thermostat for 2010 Mazda B4000
A-Premium®Part # APTHE094
Engine Coolant Thermostat for 2010 Mazda B4000
4.798 Reviews
$17.99
Low stock: Only 2 left
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits 2010 Mazda B4000
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mazda
Item LocatedUnited States
Quantity1
ConditionNew
item #10188R2E
Note
Start to Open Temperature: 87℃.
Show less
Engine Coolant Thermostat for 2017-2022 Mazda CX-5
A-Premium®Part # APTHE024
Engine Coolant Thermostat for 2017-2022 Mazda CX-5
4.798 Reviews
$26.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mazda CX-5: 2017 2018 2019 2020 2021 2022
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mazda
Item LocatedUnited States
Quantity1
ConditionNew
item #1014GPCC
Note
Start to Open Temperature: 71℃.
Show less
Engine Coolant Thermostat for 2002-2003 Mazda Protege5
A-Premium®Part # APTHE043
Engine Coolant Thermostat for 2002-2003 Mazda Protege5
4.798 Reviews
$24.99
Low stock: Only 3 left
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mazda Protege5: 2002 2003
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mazda
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1012NK60
Show less
Engine Coolant Thermostat for 2002-2003 Mazda Protege5
A-Premium®Part # APTHE023
Engine Coolant Thermostat for 2002-2003 Mazda Protege5
4.798 Reviews
$26.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mazda Protege5: 2002 2003
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mazda
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1012NCD8
Show less
Engine Coolant Thermostat for 1995-1996 Mazda Millenia
A-Premium®Part # APTHE094
Engine Coolant Thermostat for 1995-1996 Mazda Millenia
4.798 Reviews
$17.99
Low stock: Only 2 left
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mazda Millenia: 1995 1996
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mazda
Item LocatedUnited States
Quantity1
ConditionNew
item #10188Q6U
Note
Start to Open Temperature: 87℃.
Show less
Engine Coolant Thermostat for 2022-2023 Mazda CX-30
A-Premium®Part # APTHE024
Engine Coolant Thermostat for 2022-2023 Mazda CX-30
4.798 Reviews
$26.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mazda CX-30: 2022 2023
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mazda
Item LocatedUnited States
Quantity1
ConditionNew
item #1014GU0L
Note
Start to Open Temperature: 71℃.
Show less
Engine Coolant Thermostat for 1992-1995 Mazda MX-3
A-Premium®Part # APTHE043
Engine Coolant Thermostat for 1992-1995 Mazda MX-3
4.798 Reviews
$24.99
Low stock: Only 3 left
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mazda MX-3: 1992 1993 1994 1995
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mazda
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1012NK4V
Show less
Engine Coolant Thermostat for 1992-1995 Mazda MX-3
A-Premium®Part # APTHE023
Engine Coolant Thermostat for 1992-1995 Mazda MX-3
4.798 Reviews
$26.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mazda MX-3: 1992 1993 1994 1995
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mazda
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1012NH7U
Show less
Aluminum Thermostat Housing Assy with 2 Sensor for 2001-2008 Mazda B4000
A-Premium®Part # APTHA0399
Aluminum Thermostat Housing Assy with 2 Sensor for 2001-2008 Mazda B4000
4.798 Reviews
$58.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mazda B4000: 2001 2002 2003 2004 2005 2006 2007 2008
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mazda
Item LocatedUnited States
Quantity1
ConditionNew
item #101968SA
Note
This item comes with 2 Sensors.
Show less
Engine Coolant Thermostat for 2018-2020 Mazda 6
A-Premium®Part # APTHE024
Engine Coolant Thermostat for 2018-2020 Mazda 6
4.798 Reviews
$26.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mazda 6: 2018 2019 2020
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mazda
Item LocatedUnited States
Quantity1
ConditionNew
item #1014GQ27
Note
Start to Open Temperature: 71℃.
Show less
Page 3 of 6

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.

Related Blogs

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Learn why coolant boils or bubbles after you turn the engine off, how heat soak affects the cooling system, and how to diagnose leaks, trapped air, cap, thermostat, fan, water pump, or head gasket problems.

Jul 29, 2026