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Toyota Corolla Thermostat

23 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 Toyota Camry 1988-2017 RAV4 Corolla Tacoma HighlanderEngine Coolant Thermostat for Toyota Camry 1988-2017 RAV4 Corolla Tacoma Highlander
A-Premium®Part # APTHE100
Engine Coolant Thermostat for Toyota Camry 1988-2017 RAV4 Corolla Tacoma Highlander
4.685 Reviews
$16.99
Low stock: Only 1 left
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2-year warranty
90 days free return
Fits 1998 - 2002 Chevrolet Prizm, 1992 - 1992 Dodge Colt, 1993 - 1996 Eagle Summit, 1995 - 1998 Eagle Talon, 1996 - 1999 Ford Taurus, 1990 - 1991 Lexus ES250, 1992 - 2003 Lexus ES300, 2004 - 2006 Lexus ES330, 2007 - 2018 Lexus ES350, 2010 - 2012 Lexus HS250h, 1990 - 1997 Lexus LS400, 1999 - 2003 Lexus RX300, 2004 - 2006 Lexus RX330, 2007 - 2015 Lexus RX350, 2006 - 2008 Lexus RX400h, 2010 - 2015 Lexus RX450h, 1992 - 1997 Lexus SC400, 1995 - 1996 Mitsubishi Eclipse, 1996 - 1998 Mitsubishi Eclipse, 1999 - 1999 Mitsubishi Eclipse
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota Corolla
Item LocatedUnited States
Quantity1
ConditionNew
item #1018A699
Note
Start to Open Temperature: 82℃.
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A-Premium APTHE018 Engine Coolant Thermostat
A-Premium®Part # APTHE018
A-Premium APTHE018 Engine Coolant Thermostat
4.685 Reviews
$17.99
Edit ZIP code
2-year warranty
90 days free return
Fits 1985 - 1988 Chevrolet Nova, 2008 - 2009 Ford F-650, 2008 - 2009 Ford F-750, 1998 - 1998 Ford F-800, 1998 - 1998 Ford F-800 LPO, 1989 - 1997 Geo Prizm, 1993 - 1997 Geo Prizm, 1995 - 1995 Nissan 200SX, 1997 - 1998 Nissan 200SX, 1991 - 1993 Nissan NX, 1989 - 1990 Nissan Pulsar NX, 1989 - 1999 Nissan Sentra, 1996 - 1997 Nissan Sentra, 1984 - 1986 Toyota Camry, 1983 - 1991 Toyota Camry, 1992 - 2001 Toyota Camry, 1990 - 1993 Toyota Celica, 1994 - 1997 Toyota Celica, 1986 - 1989 Toyota Celica, 1992 - 1999 Toyota Celica
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota Corolla
Item LocatedUnited States
Quantity1
MaterialMetal
ConditionNew
item #1005UU8S
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A-Premium APTHE017 Engine Coolant Thermostat
A-Premium®Part # APTHE017
A-Premium APTHE017 Engine Coolant Thermostat
4.685 Reviews
$17.99
Low stock: Only 5 left
Edit ZIP code
2-year warranty
90 days free return
Fits 1985 - 1988 Chevrolet Nova, 2008 - 2009 Ford F-650, 2008 - 2009 Ford F-750, 1998 - 1998 Ford F-800, 1998 - 1998 Ford F-800 LPO, 1989 - 1997 Geo Prizm, 1993 - 1997 Geo Prizm, 1995 - 1995 Nissan 200SX, 1997 - 1998 Nissan 200SX, 1991 - 1993 Nissan NX, 1989 - 1990 Nissan Pulsar NX, 1989 - 1999 Nissan Sentra, 1996 - 1997 Nissan Sentra, 1984 - 1986 Toyota Camry, 1983 - 1991 Toyota Camry, 1992 - 2001 Toyota Camry, 1990 - 1993 Toyota Celica, 1994 - 1997 Toyota Celica, 1986 - 1989 Toyota Celica, 1992 - 1999 Toyota Celica
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota Corolla
Item LocatedUnited States
Quantity1
MaterialMetal
ConditionNew
item #1005USAT
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Engine Coolant Thermostat for Toyota Camry RAV4 Ford Mitsubishi Scion Lexus 89℃
A-Premium®Part # APTHE071
Engine Coolant Thermostat for Toyota Camry RAV4 Ford Mitsubishi Scion Lexus 89℃
4.685 Reviews
$26.99
Edit ZIP code
2-year warranty
90 days free return
Fits 1998 - 2002 Chevrolet Prizm, 1992 - 1992 Dodge Colt, 1992 - 1992 Dodge Colt, 1993 - 1996 Eagle Summit, 1995 - 1998 Eagle Talon, 1996 - 1999 Ford Taurus, 1990 - 1991 Lexus ES250, 1992 - 2003 Lexus ES300, 2004 - 2006 Lexus ES330, 2007 - 2017 Lexus ES350, 2010 - 2012 Lexus HS250h, 1990 - 1997 Lexus LS400, 1999 - 2003 Lexus RX300, 2004 - 2006 Lexus RX330, 2007 - 2015 Lexus RX350, 2006 - 2008 Lexus RX400h, 2010 - 2015 Lexus RX450h, 1992 - 1997 Lexus SC400, 1995 - 1996 Mitsubishi Eclipse, 1999 - 1999 Mitsubishi Eclipse
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota Corolla
Item LocatedUnited States
Quantity1
ConditionNew
item #1013DUS4
Note
Start to Open Temperature: 89℃.
Show less
A-Premium APTHE081 Engine Coolant Thermostat
A-Premium®Part # APTHE081
A-Premium APTHE081 Engine Coolant Thermostat
4.685 Reviews
$20.99
Edit ZIP code
2-year warranty
90 days free return
Fits 1991 - 1994 Mercury Capri, 1987 - 1990 Mercury Tracer, 1991 - 1996 Mercury Tracer, 1997 - 1999 Mitsubishi 3000GT, 1983 - 1988 Mitsubishi Cordia, 1992 - 1996 Mitsubishi Diamante, 1990 - 1994 Mitsubishi Eclipse, 1992 - 1992 Mitsubishi Expo, 1985 - 1992 Mitsubishi Galant, 1983 - 1989 Mitsubishi Mighty Max, 1983 - 1989 Mitsubishi Mighty Max, 1990 - 1993 Mitsubishi Mighty Max, 1990 - 1994 Mitsubishi Mighty Max, 1995 - 1996 Mitsubishi Mighty Max, 1985 - 1989 Mitsubishi Mirage, 1985 - 1996 Mitsubishi Mirage, 1991 - 1992 Mitsubishi Mirage, 2017 - 2017 Mitsubishi Mirage, 1983 - 1989 Mitsubishi Montero, 1989 - 1994 Mitsubishi Montero
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Vehicle: Toyota Corolla
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1005V56V
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A-Premium APTHE049 Engine Coolant Thermostat
A-Premium®Part # APTHE049
A-Premium APTHE049 Engine Coolant Thermostat
4.685 Reviews
$18.99
Low stock: Only 2 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2000 - 2005 Acura EL, 1986 - 1995 Acura Integra, 1994 - 1995 Honda Accord, 1984 - 1987 Honda Civic, 2003 - 2006 Honda Civic, 1984 - 1991 Honda Civic, 2013 - 2013 Honda Civic, 1988 - 1991 Honda Civic, 1993 - 1995 Honda Civic del Sol, 1988 - 1991 Honda CRX, 2011 - 2011 Honda CR-Z, 2011 - 2011 Honda Fit, 1995 - 1995 Honda Odyssey, 1992 - 1995 Honda Prelude, 1984 - 1984 Honda Wagovan, 1986 - 1987 Honda Wagovan, 1987 - 1988 Sterling 825, 1989 - 1991 Sterling 827, 1983 - 1983 Toyota Corolla, 1981 - 1983 Toyota Pickup
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Vehicle: Toyota Corolla
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1005V0SL
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A-Premium APTHE006 Engine Coolant Thermostat
A-Premium®Part # APTHE006
A-Premium APTHE006 Engine Coolant Thermostat
4.685 Reviews
$31.99
Edit ZIP code
2-year warranty
90 days free return
Fits 1998 - 2002 Chevrolet Prizm, 1992 - 1992 Dodge Colt, 1993 - 1996 Eagle Summit, 1995 - 1998 Eagle Talon, 1996 - 1999 Ford Taurus, 1990 - 1991 Lexus ES250, 1992 - 2003 Lexus ES300, 2004 - 2006 Lexus ES330, 2007 - 2018 Lexus ES350, 2010 - 2012 Lexus HS250h, 1990 - 1997 Lexus LS400, 1999 - 2003 Lexus RX300, 2004 - 2006 Lexus RX330, 2007 - 2015 Lexus RX350, 2006 - 2008 Lexus RX400h, 2010 - 2015 Lexus RX450h, 1992 - 1997 Lexus SC400, 1995 - 1996 Mitsubishi Eclipse, 1996 - 1998 Mitsubishi Eclipse, 1999 - 1999 Mitsubishi Eclipse
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota Corolla
Item LocatedUnited States
Quantity1
MaterialMetal
ConditionNew
item #10156A30
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Thermostat Housing Assembly for Toyota Corolla Prius Prius Plug-In Lexus CT200h
A-Premium®Part # APTHA0193
Thermostat Housing Assembly for Toyota Corolla Prius Prius Plug-In Lexus CT200h
4.685 Reviews
$28.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2011 - 2017 Lexus CT200h, 2020 - 2022 Toyota Corolla, 2010 - 2022 Toyota Prius, 2019 - 2022 Toyota Prius AWD-e, 2012 - 2015 Toyota Prius Plug-In, 2017 - 2022 Toyota Prius Prime, 2012 - 2018 Toyota Prius V
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota Corolla
Item LocatedUnited States
Quantity1
MaterialPlastic
ColorBlack
item #1005GU0H
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Engine Coolant Thermostat for Toyota RAV4 Corolla C-HR Scion iM Lexus NX300h 80℃
A-Premium®Part # APTHE013
Engine Coolant Thermostat for Toyota RAV4 Corolla C-HR Scion iM Lexus NX300h 80℃
4.685 Reviews
$32.99
Low stock: Only 4 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2015 - 2021 Lexus NX300h, 2016 - 2016 Scion iM, 2018 - 2022 Toyota C-HR, 2014 - 2014 Toyota Corolla, 2014 - 2019 Toyota Corolla, 2020 - 2022 Toyota Corolla, 2017 - 2018 Toyota Corolla iM, 2016 - 2018 Toyota RAV4
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota Corolla
Item LocatedUnited States
Quantity1
ConditionNew
item #1013DXQ6
Note
Start to Open Temperature: 80℃.
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Beck/Arnley 143-0931 Engine Coolant Thermostat Housing Assembly
Beck/ArnleyPart # 143-0931
Beck/Arnley 143-0931 Engine Coolant Thermostat Housing Assembly
51 Reviews
$50.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2011-2017 Lexus CT200h, 2010-2022 Toyota Prius, 2012-2015 Toyota Prius Plug-In, 2012-2017 Toyota Prius V, 2017-2022 Toyota Prius Prime, 2019-2022 Toyota Prius AWD-e, 2020-2022 Toyota Corolla, 2023-2023 Toyota Corolla
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota Corolla
Item LocatedUnited States
Quantity1
Part interchange
143-0931
item #1000X92P
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ÜRO Parts TY0715781PRM Engine Coolant Thermostat Housing
ÜRO PartsPart # TY0715781PRM
ÜRO Parts TY0715781PRM Engine Coolant Thermostat Housing
52 Reviews
$31.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2010-2012 Lexus HS250h, 2011-2015 Scion xB, 2001-2007 Toyota Highlander, 2002-2008 Toyota Solara, 2002-2011 Toyota Camry, 2006-2008 Toyota RAV4, 2009-2013 Toyota Corolla, 2009-2013 Toyota Matrix
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota Corolla
Item LocatedUnited States
Quantity1
MaterialAluminum
ColorBlack
item #1000ZRWL
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Beck/Arnley 143-0927 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0927
Beck/Arnley 143-0927 Engine Coolant Thermostat
51 Reviews
$37.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2010-2012 Lexus HS250h, 2009-2009 Scion xD, 2010-2014 Scion xD, 2011-2016 Scion tC, 2012-2015 Scion xB, 2004-2006 Toyota Camry, 2004-2007 Toyota Highlander, 2004-2008 Toyota Solara, 2007-2008 Toyota Camry, 2009-2010 Toyota Corolla, 2009-2011 Toyota Camry, 2009-2012 Toyota RAV4, 2009-2015 Toyota Venza, 2009-2019 Toyota Highlander, 2010-2017 Toyota Camry, 2011-2012 Toyota Sienna, 2013-2014 Toyota RAV4, 2015-2018 Toyota Corolla, 2015-2018 Toyota RAV4, 2015-2018 Toyota RAV4
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota Corolla
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0927
item #1000XGQS
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Beck/Arnley 143-0688 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0688
Beck/Arnley 143-0688 Engine Coolant Thermostat
51 Reviews
$27.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1998-1998 Chevrolet Tracker, 1999-1999 Chevrolet Tracker, 1999-1999 Chevrolet Tracker, 1999-1999 Chevrolet Tracker, 1982-1985 Chrysler LeBaron, 1983-1984 Chrysler E Class, 1983-1984 Chrysler Executive Sedan, 1983-1985 Chrysler New Yorker, 1985-1985 Chrysler Executive Limousine, 1987-1989 Chrysler Conquest, 1988-1989 Chrysler New Yorker, 1989-1990 Chrysler Dynasty, 1990-1995 Chrysler LeBaron, 1971-1978 Dodge Colt, 1978-1983 Dodge Challenger, 1979-1980 Dodge Colt, 1979-1981 Dodge D50, 1979-1984 Dodge Colt, 1981-1985 Dodge Aries, 1982-1983 Dodge 400
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota Corolla
Item LocatedUnited States
Quantity1
Part interchange
143-0688
item #1000XGE3
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Beck/Arnley 143-0689 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0689
Beck/Arnley 143-0689 Engine Coolant Thermostat
51 Reviews
$23.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1998-1998 Chevrolet Tracker, 1999-1999 Chevrolet Tracker, 1999-1999 Chevrolet Tracker, 1999-1999 Chevrolet Tracker, 1982-1985 Chrysler LeBaron, 1983-1984 Chrysler E Class, 1983-1984 Chrysler Executive Sedan, 1983-1985 Chrysler New Yorker, 1985-1985 Chrysler Executive Limousine, 1987-1989 Chrysler Conquest, 1988-1989 Chrysler New Yorker, 1989-1990 Chrysler Dynasty, 1971-1978 Dodge Colt, 1978-1983 Dodge Challenger, 1979-1980 Dodge Colt, 1979-1981 Dodge D50, 1979-1984 Dodge Colt, 1981-1985 Dodge Aries, 1982-1983 Dodge 400, 1983-1983 Dodge Power Ram 50
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota Corolla
Item LocatedUnited States
Quantity1
Part interchange
143-0689
item #1000XHG9
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Beck/Arnley 143-0728 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0728
Beck/Arnley 143-0728 Engine Coolant Thermostat
51 Reviews
$30.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1985-1988 Chevrolet Nova, 1989-1997 Geo Prizm, 1989-1989 Nissan Pulsar NX, 1989-1990 Nissan Sentra, 1990-1990 Nissan Pulsar NX, 1991-1993 Nissan NX, 1991-1994 Nissan Sentra, 1995-1995 Nissan Sentra, 1995-1998 Nissan 200SX, 1996-1999 Nissan Sentra, 1980-1997 Toyota Tercel, 1983-1985 Toyota Camry, 1983-1997 Toyota Corolla, 1984-1989 Toyota Van, 1985-1989 Toyota MR2, 1986-1986 Toyota Camry, 1986-1986 Toyota Celica, 1987-1987 Toyota Camry, 1987-1989 Toyota Celica, 1988-1991 Toyota Camry
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota Corolla
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0728
item #1000XLL2
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Beck/Arnley 143-0687 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0687
Beck/Arnley 143-0687 Engine Coolant Thermostat
51 Reviews
$22.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1998-1998 Chevrolet Tracker, 1999-1999 Chevrolet Tracker, 1999-1999 Chevrolet Tracker, 1999-1999 Chevrolet Tracker, 1982-1985 Chrysler LeBaron, 1983-1984 Chrysler E Class, 1983-1984 Chrysler Executive Sedan, 1983-1985 Chrysler New Yorker, 1985-1985 Chrysler Executive Limousine, 1987-1989 Chrysler Conquest, 1988-1989 Chrysler New Yorker, 1989-1990 Chrysler Dynasty, 1971-1978 Dodge Colt, 1978-1983 Dodge Challenger, 1979-1980 Dodge Colt, 1979-1981 Dodge D50, 1979-1983 Dodge Colt, 1981-1985 Dodge Aries, 1982-1983 Dodge 400, 1983-1983 Dodge Power Ram 50
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota Corolla
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0687
item #1000XKVK
Show less
Beck/Arnley 143-0697 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0697
Beck/Arnley 143-0697 Engine Coolant Thermostat
51 Reviews
$23.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1985-1988 Chevrolet Nova, 1989-1997 Geo Prizm, 1989-1989 Nissan Pulsar NX, 1989-1990 Nissan Sentra, 1990-1990 Nissan Pulsar NX, 1991-1993 Nissan NX, 1991-1994 Nissan Sentra, 1995-1995 Nissan Sentra, 1995-1998 Nissan 200SX, 1996-1999 Nissan Sentra, 1980-1999 Toyota Tercel, 1983-1985 Toyota Camry, 1983-1997 Toyota Corolla, 1984-1989 Toyota Van, 1985-1989 Toyota MR2, 1986-1986 Toyota Camry, 1986-1986 Toyota Celica, 1987-1987 Toyota Camry, 1987-1989 Toyota Celica, 1988-1991 Toyota Camry
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota Corolla
Item LocatedUnited States
Quantity1
Part interchange
143-0697
item #1000XKK3
Show less
Beck/Arnley 143-0722 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0722
Beck/Arnley 143-0722 Engine Coolant Thermostat
51 Reviews
$44.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1998-2000 Chevrolet Prizm, 1995-1998 Eagle Talon, 1999-2005 Hyundai Sonata, 2001-2004 Hyundai Santa Fe, 2003-2006 Kia Optima, 1990-1991 Lexus ES250, 1990-1996 Lexus LS400, 1992-1995 Lexus ES300, 1992-1997 Lexus SC400, 1999-2002 Lexus ES300, 1999-2002 Lexus RX300, 2004-2004 Lexus ES330, 2007-2015 Lexus RX350, 2007-2018 Lexus ES350, 2010-2015 Lexus RX450h, 1993-1994 Mitsubishi Expo LRV, 1993-1995 Mitsubishi Expo, 1993-1998 Mitsubishi Galant, 1995-1999 Mitsubishi Eclipse, 1995-1999 Mitsubishi Eclipse
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota Corolla
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0722
item #1000XEUU
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Beck/Arnley 143-0957 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0957
Beck/Arnley 143-0957 Engine Coolant Thermostat
51 Reviews
$30.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2015-2021 Lexus NX300h, 2014-2018 Toyota Corolla, 2016-2018 Toyota RAV4, 2016-2018 Toyota RAV4, 2017-2018 Toyota Corolla iM, 2017-2018 Toyota RAV4, 2018-2021 Toyota C-HR, 2019-2022 Toyota Corolla
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota Corolla
Item LocatedUnited States
Quantity1
Part interchange
143-0957
item #1000XGN4
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Beck/Arnley 143-0654 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0654
Beck/Arnley 143-0654 Engine Coolant Thermostat
51 Reviews
$31.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1985-1988 Chevrolet Nova, 1989-1997 Geo Prizm, 1989-1989 Nissan Pulsar NX, 1989-1990 Nissan Sentra, 1990-1990 Nissan Pulsar NX, 1991-1993 Nissan NX, 1991-1994 Nissan Sentra, 1995-1995 Nissan Sentra, 1995-1998 Nissan 200SX, 1996-1999 Nissan Sentra, 1980-1997 Toyota Tercel, 1983-1985 Toyota Camry, 1983-1997 Toyota Corolla, 1984-1989 Toyota Van, 1985-1989 Toyota MR2, 1986-1986 Toyota Camry, 1986-1986 Toyota Celica, 1987-1987 Toyota Camry, 1987-1989 Toyota Celica, 1988-1991 Toyota Camry
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota Corolla
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0654
item #1000XK4S
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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