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Subaru Impreza Thermostat

11 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 Subaru Outback Forester Impreza WRX Saab 9-2X 78℃Engine Coolant Thermostat for Subaru Outback Forester Impreza WRX Saab 9-2X 78℃
A-Premium®Part # APTHE051
Engine Coolant Thermostat for Subaru Outback Forester Impreza WRX Saab 9-2X 78℃
4.685 Reviews
$22.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2005 - 2005 Saab 9-2X, 2005 - 2006 Saab 9-2X, 2003 - 2006 Subaru Baja, 1998 - 2010 Subaru Forester, 2011 - 2013 Subaru Forester, 1993 - 1997 Subaru Impreza, 2002 - 2005 Subaru Impreza, 1995 - 2001 Subaru Impreza, 1998 - 2014 Subaru Impreza, 1990 - 1999 Subaru Legacy, 1996 - 2009 Subaru Legacy, 2015 - 2019 Subaru Legacy, 2000 - 2009 Subaru Outback, 2001 - 2004 Subaru Outback, 2015 - 2019 Subaru Outback, 1992 - 1997 Subaru SVX, 2013 - 2016 Subaru WRX, 2013 - 2018 Subaru WRX STI, 2020 - 2021 Subaru WRX STI
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru Impreza
Item LocatedUnited States
Quantity1
ConditionNew
item #1013DYPS
Note
【Note-1】 Start to Open Temperature: 78℃.;
【Note-2】 2011-2013 Subaru Forester it fits Turbocharged only, NOT fit Naturally Aspirated.
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Engine Coolant Thermostat for Subaru Outback 00-15 Forester Impreza Legacy 82℃
A-Premium®Part # APTHE076
Engine Coolant Thermostat for Subaru Outback 00-15 Forester Impreza Legacy 82℃
4.685 Reviews
$23.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2005 - 2006 Saab 9-2X, 2006 - 2007 Subaru B9 Tribeca, 2003 - 2006 Subaru Baja, 2011 - 2013 Subaru Forester, 2014 - 2016 Subaru Forester, 2004 - 2010 Subaru Forester, 1995 - 1997 Subaru Impreza, 2002 - 2005 Subaru Impreza, 1995 - 2001 Subaru Impreza, 1998 - 2003 Subaru Impreza, 2004 - 2011 Subaru Impreza, 1995 - 1999 Subaru Legacy, 1996 - 2004 Subaru Legacy, 2005 - 2009 Subaru Legacy, 2008 - 2009 Subaru Legacy, 2010 - 2015 Subaru Legacy, 2000 - 2009 Subaru Outback, 2001 - 2005 Subaru Outback, 2006 - 2009 Subaru Outback, 2010 - 2015 Subaru Outback
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru Impreza
Item LocatedUnited States
Quantity1
ConditionNew
item #1013DYCR
Note
【Note-1】 Start to Open Temperature: 82℃.;
【Note-2】 2014-2016 Subaru Forester H4 2.5L with Manual Transmission or Automatic CVT Transmission.;
【Note-3】 2005 Subaru Outback H6 3.0L with model built before 05/2005.
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Engine Coolant Thermostat for Subaru Outback Forester Impreza Legacy Tribeca 60℃
A-Premium®Part # APTHE073
Engine Coolant Thermostat for Subaru Outback Forester Impreza Legacy Tribeca 60℃
4.685 Reviews
$20.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2006 - 2007 Subaru B9 Tribeca, 2003 - 2006 Subaru Baja, 1998 - 2013 Subaru Forester, 1993 - 1997 Subaru Impreza, 2002 - 2005 Subaru Impreza, 2008 - 2011 Subaru Impreza, 1995 - 2001 Subaru Impreza, 1998 - 2014 Subaru Impreza, 2008 - 2009 Subaru Legacy, 1990 - 1999 Subaru Legacy, 1996 - 2009 Subaru Legacy, 2010 - 2012 Subaru Legacy, 2008 - 2009 Subaru Legacy, 2010 - 2019 Subaru Legacy, 2000 - 2012 Subaru Outback, 2001 - 2009 Subaru Outback, 2017 - 2017 Subaru Outback, 2019 - 2019 Subaru Outback, 2010 - 2016 Subaru Outback, 1992 - 1997 Subaru SVX
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru Impreza
Item LocatedUnited States
Quantity1
ConditionNew
item #1013DXAA
Note
【Note-1】 Start to Open Temperature: 60℃.
【Note-2】 2010-2012 Subaru Legacy H4 2.5L fit Naturally Aspirated only, NOT fit Turbocharged.
【Note-3】 2017 Subaru Outback H6 3.6L fit 3.6R Touring Model only, NOT fit 3.6R Limited or 3.6R Premium.
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Engine Coolant Thermostat for Subaru Outback Forester Impreza Legacy Tribeca 77℃
A-Premium®Part # APTHE074
Engine Coolant Thermostat for Subaru Outback Forester Impreza Legacy Tribeca 77℃
4.685 Reviews
$22.99
Low stock: Only 4 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2006 - 2007 Subaru B9 Tribeca, 2003 - 2006 Subaru Baja, 1998 - 2013 Subaru Forester, 1993 - 1997 Subaru Impreza, 2002 - 2005 Subaru Impreza, 2008 - 2011 Subaru Impreza, 1995 - 2001 Subaru Impreza, 1998 - 2014 Subaru Impreza, 2008 - 2009 Subaru Legacy, 1990 - 1999 Subaru Legacy, 1996 - 2009 Subaru Legacy, 2010 - 2012 Subaru Legacy, 2008 - 2009 Subaru Legacy, 2010 - 2013 Subaru Legacy, 2015 - 2019 Subaru Legacy, 2000 - 2012 Subaru Outback, 2001 - 2009 Subaru Outback, 2017 - 2017 Subaru Outback, 2019 - 2019 Subaru Outback, 2010 - 2013 Subaru Outback
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru Impreza
Item LocatedUnited States
Quantity1
ConditionNew
item #1013DW8U
Note
【Note-1】 Start to Open Temperature: 77℃.
【Note-2】 2010-2012 Subaru Legacy H4 2.5L fit Naturally Aspirated only, NOT fit Turbocharged.
【Note-3】 2017 Subaru Outback H6 3.6L fit 3.6R Touring Model only, NOT fit 3.6R Limited or 3.6R Premium.
Show less
Engine Coolant Thermostat for Subaru Outback 13-19 Forester Impreza Toyota 89℃
A-Premium®Part # APTHE068
Engine Coolant Thermostat for Subaru Outback 13-19 Forester Impreza Toyota 89℃
4.685 Reviews
$20.99
Low stock: Only 3 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2011 - 2015 Mitsubishi Lancer, 2011 - 2015 Mitsubishi Lancer, 2016 - 2017 Mitsubishi Lancer, 2011 - 2020 Mitsubishi Outlander, 2018 - 2018 Mitsubishi Outlander, 2018 - 2020 Mitsubishi Outlander PHEV, 2011 - 2021 Mitsubishi Outlander Sport, 2015 - 2020 Mitsubishi Outlander Sport, 2011 - 2017 Mitsubishi RVR, 2013 - 2013 Scion FR-S, 2014 - 2016 Scion FR-S, 2013 - 2020 Subaru BRZ, 2016 - 2021 Subaru Crosstrek, 2011 - 2023 Subaru Forester, 2012 - 2014 Subaru Impreza, 2015 - 2021 Subaru Impreza, 2022 - 2023 Subaru Impreza, 2013 - 2014 Subaru Legacy, 2015 - 2019 Subaru Legacy, 2013 - 2014 Subaru Outback
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru Impreza
Item LocatedUnited States
Quantity1
ConditionNew
item #1013DVR7
Note
Start to Open Temperature: 89℃.
Show less
Engine Coolant Thermostat for Subaru Outback 13-19 Forester Mitsubishi Scion 87℃
A-Premium®Part # APTHE067
Engine Coolant Thermostat for Subaru Outback 13-19 Forester Mitsubishi Scion 87℃
4.685 Reviews
$23.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2011 - 2015 Mitsubishi Lancer, 2011 - 2016 Mitsubishi Lancer, 2016 - 2016 Mitsubishi Lancer, 2017 - 2017 Mitsubishi Lancer, 2017 - 2017 Mitsubishi Lancer, 2017 - 2017 Mitsubishi Lancer, 2017 - 2017 Mitsubishi Lancer, 2017 - 2017 Mitsubishi Lancer, 2017 - 2017 Mitsubishi Lancer, 2017 - 2017 Mitsubishi Lancer, 2011 - 2020 Mitsubishi Outlander, 2018 - 2018 Mitsubishi Outlander, 2022 - 2022 Mitsubishi Outlander, 2018 - 2021 Mitsubishi Outlander PHEV, 2022 - 2023 Mitsubishi Outlander PHEV, 2011 - 2016 Mitsubishi Outlander Sport, 2015 - 2016 Mitsubishi Outlander Sport, 2017 - 2017 Mitsubishi Outlander, 2017 - 2017 Mitsubishi Outlander, 2017 - 2017 Mitsubishi Outlander
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru Impreza
Item LocatedUnited States
Quantity1
ConditionNew
item #1013DV7W
Note
Start to Open Temperature: 87℃.
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Beck/Arnley 143-0923 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0923
Beck/Arnley 143-0923 Engine Coolant Thermostat
51 Reviews
$29.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2012-2014 Subaru Impreza, 2012-2014 Subaru Impreza, 2012-2014 Subaru Impreza, 2012-2014 Subaru Impreza, 2012-2014 Subaru Impreza, 2012-2014 Subaru Impreza, 2012-2014 Subaru Impreza, 2013-2013 Subaru Legacy, 2013-2013 Subaru Legacy, 2013-2013 Subaru Legacy, 2013-2013 Subaru Legacy, 2013-2013 Subaru Legacy, 2013-2013 Subaru Outback, 2013-2014 Subaru Outback, 2013-2014 Subaru Outback, 2013-2014 Subaru Outback, 2013-2014 Subaru Outback, 2013-2014 Subaru XV Crosstrek, 2014-2014 Subaru Legacy, 2014-2014 Subaru Outback
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru Impreza
Item LocatedUnited States
Quantity1
Part interchange
143-0923
item #1000XKE6
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Beck/Arnley 143-0972 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0972
Beck/Arnley 143-0972 Engine Coolant Thermostat
51 Reviews
$24.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2015-2015 Subaru Outback, 2015-2015 Subaru Outback, 2015-2015 Subaru Outback, 2015-2015 Subaru Outback, 2015-2015 Subaru Outback, 2015-2015 Subaru Outback, 2015-2015 Subaru XV Crosstrek, 2015-2015 Subaru XV Crosstrek, 2015-2015 Subaru XV Crosstrek, 2015-2016 Subaru Impreza, 2015-2019 Subaru Legacy, 2016-2016 Subaru Crosstrek, 2016-2016 Subaru Crosstrek, 2016-2016 Subaru Crosstrek, 2016-2019 Subaru Outback, 2017-2017 Subaru Crosstrek
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru Impreza
Item LocatedUnited States
Quantity1
Part interchange
143-0972
item #1000XDXG
Show less
Beck/Arnley 143-0710 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0710
Beck/Arnley 143-0710 Engine Coolant Thermostat
51 Reviews
$36.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1990-2004 Subaru Legacy, 1992-1997 Subaru SVX, 1993-2001 Subaru Impreza, 1998-2010 Subaru Forester, 2000-2009 Subaru Outback, 2002-2004 Subaru Impreza, 2002-2005 Subaru Impreza, 2002-2005 Subaru Impreza, 2003-2006 Subaru Baja, 2004-2007 Subaru Impreza, 2005-2005 Subaru Legacy, 2005-2005 Subaru Legacy, 2006-2007 Subaru B9 Tribeca, 2006-2007 Subaru Impreza, 2006-2007 Subaru Impreza, 2006-2007 Subaru Impreza, 2006-2009 Subaru Legacy, 2006-2009 Subaru Legacy, 2007-2007 Subaru Impreza, 2007-2009 Subaru Legacy
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru Impreza
Item LocatedUnited States
Quantity1
Part interchange
143-0710
item #1000XH8Z
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Engine Coolant Thermostat - Upper - Mahle TX 258 55
MahlePart # TX 258 55
Engine Coolant Thermostat - Upper - Mahle TX 258 55
51 Reviews
$30.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2012-2015 Subaru Impreza, 2012-2016 Subaru Impreza, 2012-2016 Subaru Impreza, 2012-2016 Subaru Impreza, 2012-2016 Subaru Impreza, 2012-2016 Subaru Impreza, 2012-2016 Subaru Impreza, 2013-2015 Subaru BRZ, 2013-2015 Subaru XV Crosstrek, 2014-2016 Subaru Forester, 2015-2015 Subaru Legacy, 2015-2015 Subaru Outback, 2015-2015 Subaru Outback, 2015-2015 Subaru Outback, 2015-2015 Subaru Outback, 2015-2015 Subaru Outback, 2015-2015 Subaru Outback
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru Impreza
Item LocatedUnited States
Quantity1
Installation PositionUpper
Part interchange
TX 258 55, TX 258 55, 21210 AA190
item #1000XQTQ
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Engine Coolant Thermostat - Mahle TX 143 78D
MahlePart # TX 143 78D
Engine Coolant Thermostat - Mahle TX 143 78D
51 Reviews
$28.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1990-2007 Subaru Legacy, 1992-1997 Subaru SVX, 1993-2007 Subaru Impreza, 1999-2010 Subaru Forester, 2000-2009 Subaru Outback, 2003-2006 Subaru Baja, 2006-2007 Subaru B9 Tribeca, 2008-2009 Subaru Legacy, 2008-2009 Subaru Legacy, 2008-2014 Subaru Impreza, 2008-2014 Subaru Tribeca, 2010-2015 Subaru Legacy, 2010-2015 Subaru Outback, 2011-2011 Subaru Forester, 2011-2012 Subaru Forester, 2011-2012 Subaru Forester, 2011-2012 Subaru Forester, 2011-2013 Subaru Forester, 2011-2013 Subaru Forester, 2012-2013 Subaru Forester
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru Impreza
Item LocatedUnited States
Quantity1
Part interchange
TX 143 78D, 410230.78D, 33857, 48457, TX14378D, 294-170, 21200 AA072, 21200 AA071, 
...View more
item #1000XNE1
Show less

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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