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Subaru Thermostat

21 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℃
4.692 Reviews
$22.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2020 - 2021 Subaru WRX STI, 2015 - 2019 Subaru Legacy, 2015 - 2019 Subaru Outback, 2013 - 2018 Subaru WRX STI, 2013 - 2016 Subaru WRX, 2011 - 2013 Subaru Forester, 2005 - 2006 Saab 9-2X, 2005 - 2005 Saab 9-2X, 2003 - 2006 Subaru Baja, 2002 - 2005 Subaru Impreza, 2001 - 2004 Subaru Outback, 2000 - 2009 Subaru Outback, 1998 - 2014 Subaru Impreza, 1998 - 2010 Subaru Forester, 1996 - 2009 Subaru Legacy, 1995 - 2001 Subaru Impreza, 1993 - 1997 Subaru Impreza, 1992 - 1997 Subaru SVX, 1990 - 1999 Subaru Legacy
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
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℃
4.692 Reviews
$23.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2014 - 2016 Subaru Forester, 2011 - 2013 Subaru Forester, 2010 - 2015 Subaru Legacy, 2010 - 2015 Subaru Outback, 2008 - 2014 Subaru Tribeca, 2008 - 2009 Subaru Legacy, 2006 - 2009 Subaru Outback, 2006 - 2007 Subaru B9 Tribeca, 2005 - 2009 Subaru Legacy, 2005 - 2006 Saab 9-2X, 2004 - 2011 Subaru Impreza, 2004 - 2010 Subaru Forester, 2003 - 2006 Subaru Baja, 2002 - 2005 Subaru Impreza, 2001 - 2005 Subaru Outback, 2000 - 2009 Subaru Outback, 1998 - 2003 Subaru Impreza, 1996 - 2004 Subaru Legacy, 1995 - 2001 Subaru Impreza, 1995 - 1999 Subaru Legacy
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
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℃
4.692 Reviews
$20.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2019 - 2019 Subaru Outback, 2017 - 2017 Subaru Outback, 2013 - 2020 Subaru WRX STI, 2013 - 2014 Subaru WRX, 2010 - 2019 Subaru Legacy, 2010 - 2016 Subaru Outback, 2010 - 2012 Subaru Legacy, 2008 - 2014 Subaru Tribeca, 2008 - 2011 Subaru Impreza, 2008 - 2009 Subaru Legacy, 2008 - 2009 Subaru Legacy, 2006 - 2007 Subaru B9 Tribeca, 2003 - 2006 Subaru Baja, 2002 - 2005 Subaru Impreza, 2001 - 2009 Subaru Outback, 2000 - 2012 Subaru Outback, 1998 - 2014 Subaru Impreza, 1998 - 2013 Subaru Forester, 1996 - 2009 Subaru Legacy, 1995 - 2001 Subaru Impreza
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
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.
Show less
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℃
4.692 Reviews
$22.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2019 - 2019 Subaru Outback, 2017 - 2017 Subaru Outback, 2015 - 2019 Subaru Legacy, 2015 - 2016 Subaru Outback, 2013 - 2021 Subaru WRX STI, 2013 - 2016 Subaru WRX, 2010 - 2013 Subaru Legacy, 2010 - 2013 Subaru Outback, 2010 - 2012 Subaru Legacy, 2008 - 2013 Subaru Tribeca, 2008 - 2011 Subaru Impreza, 2008 - 2009 Subaru Legacy, 2008 - 2009 Subaru Legacy, 2006 - 2007 Subaru B9 Tribeca, 2003 - 2006 Subaru Baja, 2002 - 2005 Subaru Impreza, 2001 - 2009 Subaru Outback, 2000 - 2012 Subaru Outback, 1998 - 2014 Subaru Impreza, 1998 - 2013 Subaru Forester
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
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 GMC S15 Isuzu Oldsmobile Pontiac Subaru Suzuki 91℃
A-Premium®Part # APTHE078
Engine Coolant Thermostat for GMC S15 Isuzu Oldsmobile Pontiac Subaru Suzuki 91℃
4.692 Reviews
$20.99
Low stock: Only 1 left
Edit ZIP code
2-year warranty
90 days free return
Fits 1996 - 2003 GMC Sonoma, 1996 - 2000 Isuzu Hombre, 1996 - 1997 GMC P3500, 1996 - 1996 Oldsmobile Cutlass, 1996 - 1996 Pontiac Grand, 1995 - 2000 Pontiac Firefly, 1995 - 2000 Pontiac Firefly, 1995 - 2000 Suzuki Esteem, 1995 - 1997 Pontiac Firebird, 1995 - 1995 GMC Jimmy, 1995 - 1995 GMC Safari, 1995 - 1995 Pontiac Sunfire, 1994 - 1995 GMC Sonoma, 1994 - 1994 Suzuki Swift, 1993 - 1996 GMC G3500, 1993 - 1996 Oldsmobile Cutlass, 1993 - 1995 Pontiac Firebird, 1993 - 1994 Oldsmobile Bravada, 1992 - 1995 GMC C2500 Suburban, 1992 - 1995 GMC K2500 Suburban
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
ConditionNew
item #1013DTRR
Note
Start to Open Temperature: 91℃.
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℃
4.692 Reviews
$20.99
Low stock: Only 4 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2022 - 2024 Toyota GR86, 2022 - 2023 Subaru Impreza, 2018 - 2020 Mitsubishi Outlander PHEV, 2018 - 2018 Mitsubishi Outlander, 2018 - 2018 Subaru Outback, 2017 - 2020 Toyota 86, 2017 - 2017 Subaru Outback, 2016 - 2021 Subaru Crosstrek, 2016 - 2017 Mitsubishi Lancer, 2015 - 2021 Subaru Impreza, 2015 - 2020 Mitsubishi Outlander Sport, 2015 - 2019 Subaru Legacy, 2015 - 2019 Subaru Outback, 2014 - 2016 Scion FR-S, 2013 - 2020 Subaru BRZ, 2013 - 2015 Subaru XV Crosstrek, 2013 - 2014 Subaru Legacy, 2013 - 2014 Subaru Outback, 2013 - 2013 Scion FR-S, 2012 - 2014 Subaru Impreza
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
ConditionNew
item #1013DVR7
Note
Start to Open Temperature: 89℃.
Show less
Beck/Arnley 143-0930 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0930
Beck/Arnley 143-0930 Engine Coolant Thermostat
52 Reviews
$40.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2010-2012 Subaru Legacy, 2010-2012 Subaru Outback
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
143-0930
item #1000XKVU
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Beck/Arnley 143-0686 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0686
Beck/Arnley 143-0686 Engine Coolant Thermostat
52 Reviews
$19.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1994-1996 Honda Passport, 1993-1993 Isuzu Stylus, 1992-1993 Geo Storm, 1992-1992 Isuzu Impulse, 1992-1992 Isuzu Stylus, 1991-1997 Isuzu Rodeo, 1991-1991 Isuzu Stylus, 1990-1994 Subaru Loyale, 1990-1991 Geo Storm, 1989-1994 Isuzu Amigo, 1989-1991 Isuzu Trooper, 1989-1989 Geo Spectrum, 1989-1989 Nissan Pulsar NX, 1988-1995 Isuzu Pickup, 1988-1995 Isuzu Pickup, 1988-1990 Isuzu Pickup, 1988-1989 Subaru GL, 1988-1988 Isuzu Trooper, 1987-1988 Nissan 200SX, 1987-1988 Nissan Van
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0686
item #1000XHZN
Show less
Beck/Arnley 143-0923 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0923
Beck/Arnley 143-0923 Engine Coolant Thermostat
52 Reviews
$29.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2016-2016 Subaru Crosstrek, 2016-2016 Subaru Crosstrek, 2015-2015 Subaru XV Crosstrek, 2015-2015 Subaru XV Crosstrek, 2014-2014 Subaru Legacy, 2014-2014 Subaru Outback, 2014-2014 Subaru Outback, 2013-2014 Subaru Outback, 2013-2014 Subaru Outback, 2013-2014 Subaru Outback, 2013-2014 Subaru Outback, 2013-2014 Subaru XV Crosstrek, 2013-2013 Subaru Legacy, 2013-2013 Subaru Legacy, 2013-2013 Subaru Legacy, 2013-2013 Subaru Legacy, 2013-2013 Subaru Legacy, 2013-2013 Subaru Outback, 2012-2014 Subaru Impreza, 2012-2014 Subaru Impreza
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
143-0923
item #1000XKE6
Show less
Beck/Arnley 143-0684 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0684
Beck/Arnley 143-0684 Engine Coolant Thermostat
52 Reviews
$20.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1995-1995 Isuzu Pickup, 1994-1996 Honda Passport, 1993-1993 Isuzu Stylus, 1992-1993 Geo Storm, 1992-1992 Isuzu Impulse, 1992-1992 Isuzu Stylus, 1991-1997 Isuzu Rodeo, 1991-1994 Isuzu Pickup, 1991-1994 Isuzu Pickup, 1991-1991 Isuzu Stylus, 1990-1994 Subaru Loyale, 1990-1991 Geo Storm, 1989-1994 Isuzu Amigo, 1989-1991 Isuzu Trooper, 1989-1989 Geo Spectrum, 1989-1989 Nissan Pulsar NX, 1988-1990 Isuzu Pickup, 1988-1989 Subaru GL, 1988-1988 Isuzu Trooper, 1987-1988 Nissan 200SX
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
143-0684
item #1000XKL4
Show less
Beck/Arnley 143-0912 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0912
Beck/Arnley 143-0912 Engine Coolant Thermostat
52 Reviews
$29.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2017-2020 Toyota 86, 2014-2018 Subaru Forester, 2013-2016 Scion FR-S, 2013-2015 Subaru BRZ, 2013-2013 Subaru Forester, 2012-2013 Subaru Forester, 2011-2013 Subaru Forester, 2011-2013 Subaru Forester, 2011-2013 Subaru Forester, 2011-2011 Subaru Forester
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
143-0912
item #1000XLDD
Show less
Beck/Arnley 143-0694 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0694
Beck/Arnley 143-0694 Engine Coolant Thermostat
52 Reviews
$21.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1999-2000 Suzuki Esteem, 1998-2000 Chevrolet Metro, 1995-1999 Suzuki Swift, 1995-1998 Suzuki Esteem, 1995-1997 Geo Metro, 1992-1994 Suzuki Swift, 1991-1994 Isuzu Pickup, 1991-1992 Isuzu Rodeo, 1989-1993 Geo Metro, 1989-1991 Suzuki Swift, 1987-1991 Subaru Justy, 1984-1991 Nissan Micra
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0694
item #1000XLD4
Show less
Beck/Arnley 143-0685 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0685
Beck/Arnley 143-0685 Engine Coolant Thermostat
52 Reviews
$19.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1994-1996 Honda Passport, 1993-1993 Isuzu Stylus, 1992-1993 Geo Storm, 1992-1992 Isuzu Impulse, 1992-1992 Isuzu Stylus, 1991-1997 Isuzu Rodeo, 1991-1991 Isuzu Stylus, 1990-1994 Subaru Loyale, 1990-1991 Geo Storm, 1989-1994 Isuzu Amigo, 1989-1991 Isuzu Trooper, 1989-1989 Geo Spectrum, 1989-1989 Nissan Pulsar NX, 1988-1995 Isuzu Pickup, 1988-1995 Isuzu Pickup, 1988-1990 Isuzu Pickup, 1988-1989 Subaru GL, 1988-1988 Isuzu Trooper, 1987-1988 Nissan 200SX, 1987-1988 Nissan Van
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
143-0685
item #1000XH1H
Show less
Beck/Arnley 143-0972 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0972
Beck/Arnley 143-0972 Engine Coolant Thermostat
52 Reviews
$24.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2017-2017 Subaru Crosstrek, 2016-2019 Subaru Outback, 2016-2016 Subaru Crosstrek, 2016-2016 Subaru Crosstrek, 2016-2016 Subaru Crosstrek, 2015-2019 Subaru Legacy, 2015-2016 Subaru Impreza, 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
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
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
52 Reviews
$36.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2015-2015 Subaru WRX STI, 2012-2013 Subaru Forester, 2011-2013 Subaru Forester, 2011-2013 Subaru Forester, 2011-2012 Subaru Forester, 2010-2017 Subaru Outback, 2010-2015 Subaru Legacy, 2010-2011 Subaru Impreza, 2010-2010 Subaru Impreza, 2009-2011 Subaru Impreza, 2009-2011 Subaru Impreza, 2009-2011 Subaru Impreza, 2009-2009 Subaru Legacy, 2009-2009 Subaru Legacy, 2008-2014 Subaru Tribeca, 2008-2009 Subaru Legacy, 2008-2008 Subaru Impreza, 2008-2008 Subaru Legacy, 2008-2008 Subaru Legacy, 2007-2009 Subaru Legacy
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
143-0710
item #1000XH8Z
Show less
Beck/Arnley 143-0951 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0951
Beck/Arnley 143-0951 Engine Coolant Thermostat
52 Reviews
$31.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2020-2020 Subaru Legacy, 2020-2020 Subaru Outback, 2019-2020 Subaru Ascent, 2017-2020 Subaru WRX, 2015-2016 Subaru WRX, 2014-2018 Subaru Forester
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
143-0951
item #1000XKAZ
Show less
Beck/Arnley 143-0727 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0727
Beck/Arnley 143-0727 Engine Coolant Thermostat
52 Reviews
$22.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1999-2000 Suzuki Esteem, 1998-2000 Chevrolet Metro, 1995-2001 Suzuki Swift, 1995-1998 Suzuki Esteem, 1995-1997 Geo Metro, 1992-1994 Suzuki Swift, 1991-1994 Isuzu Pickup, 1991-1992 Isuzu Rodeo, 1990-1991 Isuzu Trooper, 1989-1993 Geo Metro, 1989-1991 Suzuki Swift, 1987-1991 Subaru Justy, 1984-1991 Nissan Micra
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0727
item #1000XGS4
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℃
4.692 Reviews
$23.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2022 - 2023 Mitsubishi Outlander PHEV, 2022 - 2023 Subaru Impreza, 2022 - 2022 Mitsubishi Outlander, 2021 - 2021 Subaru Crosstrek, 2018 - 2023 Mitsubishi Outlander Sport, 2018 - 2021 Mitsubishi Outlander PHEV, 2018 - 2020 Mitsubishi Outlander Sport, 2018 - 2018 Mitsubishi Outlander, 2018 - 2018 Subaru Outback, 2017 - 2019 Toyota 86, 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, 2017 - 2017 Mitsubishi Outlander, 2017 - 2017 Mitsubishi Outlander, 2017 - 2017 Mitsubishi Outlander
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
ConditionNew
item #1013DV7W
Note
Start to Open Temperature: 87℃.
Show less
Engine Coolant Thermostat - Mahle TX 113 88D
MahlePart # TX 113 88D
Engine Coolant Thermostat - Mahle TX 113 88D
51 Reviews
$29.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1999-2000 Suzuki Esteem, 1995-1998 Suzuki Esteem, 1989-2001 Suzuki Swift, 1989-1992 Daihatsu Charade, 1989-1991 Isuzu Trooper, 1988-1988 Daihatsu Charade, 1987-1991 Subaru Justy
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
TX 113 88D, 410183.88D, 34019, 48529, TX11388D, 203-195, 17600-85821, 17670-50G10
item #1000XS00
Show less
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 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, 2014-2016 Subaru Forester, 2013-2015 Subaru BRZ, 2013-2015 Subaru XV Crosstrek, 2012-2016 Subaru Impreza, 2012-2016 Subaru Impreza, 2012-2016 Subaru Impreza, 2012-2016 Subaru Impreza, 2012-2016 Subaru Impreza, 2012-2016 Subaru Impreza, 2012-2015 Subaru Impreza
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Installation PositionUpper
Part interchange
TX 258 55, TX 258 55, 21210 AA190
item #1000XQTQ
Show less
Page 1 of 2

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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