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Audi S4 Thermostat

18 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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Thermostat Housing Assembly with Seal for Audi A5 Quattro 2012-2014 Q5 13-17 3.0LThermostat Housing Assembly with Seal for Audi A5 Quattro 2012-2014 Q5 13-17 3.0L
A-Premium®Part # APTHA0047
Thermostat Housing Assembly with Seal for Audi A5 Quattro 2012-2014 Q5 13-17 3.0L
4.693 Reviews
$39.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits 2017 - 2017 Audi Q5, 2017 - 2017 Audi SQ5, 2015 - 2015 Audi A5, 2014 - 2016 Audi SQ5, 2013 - 2016 Audi Q5, 2013 - 2014 Audi A4 Quattro, 2012 - 2014 Audi A5 Quattro, 2012 - 2014 Audi A7 Quattro, 2012 - 2013 Audi A8 Quattro, 2012 - 2012 Audi S4, 2011 - 2017 Volkswagen Touareg, 2011 - 2015 Audi Q7, 2009 - 2014 Audi A6 Quattro
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Vehicle: Audi S4
Item LocatedUnited States
Quantity1
ColorBlack
ConditionNew
item #1003CYEH
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Engine Coolant Thermostat for Jeep XJ Cherokee 1985-1987 Lincoln Continental
A-Premium®Part # APTHA348PG
Engine Coolant Thermostat for Jeep XJ Cherokee 1985-1987 Lincoln Continental
4.693 Reviews
$20.99
Low stock: Only 4 left
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits 2002 - 2008 Audi A8 Quattro, 1998 - 1999 BMW Z3, 1996 - 1998 Mercedes-Benz E300, 1995 - 1997 Jaguar XJR, 1995 - 1996 Audi S6, 1995 - 1995 BMW M3, 1994 - 1996 Jaguar XJS, 1994 - 1995 Mercedes-Benz S350, 1993 - 1993 BMW 525iT, 1993 - 1993 Jaguar XJRS, 1992 - 1994 Audi S4, 1992 - 1993 Mercedes-Benz 300SD, 1991 - 1993 BMW M5, 1991 - 1992 Audi 80, 1991 - 1991 Mercedes-Benz 350SD, 1990 - 1997 Jaguar Vanden Plas, 1990 - 1997 Jaguar XJ6, 1990 - 1993 Mercedes-Benz 300D, 1990 - 1991 Audi Coupe Quattro, 1990 - 1991 Mercedes-Benz 350SDL
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Vehicle: Audi S4
Item LocatedUnited States
Quantity1
ConditionNew
item #1018A76Z
Note
Start to Open Temperature: 80℃.
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Vaico V10-9709 Engine Coolant Thermostat Housing
VaicoPart # V10-9709
Vaico V10-9709 Engine Coolant Thermostat Housing
4.17 Reviews
$12.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 1995-1995 Audi S6, 1995-1995 Volkswagen EuroVan, 1993-1993 Volkswagen EuroVan, 1993-1993 Volkswagen EuroVan, 1993-1993 Volkswagen EuroVan, 1992-1994 Audi S4
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Vehicle: Audi S4
Item LocatedUnited States
Quantity1
Part interchange
V10-9709, 74121121, 074121121, 074121121B, 74121121B, 902983, 1470060
item #100106Z0
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Vemo V15-99-2081 Engine Coolant Thermostat
VemoPart # V15-99-2081
Vemo V15-99-2081 Engine Coolant Thermostat
57 Reviews
$102.99
Low stock: Only 3 left
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2017-2017 Audi Q5, 2017-2017 Audi S5, 2017-2017 Audi S5, 2017-2017 Audi S5, 2017-2017 Audi SQ5, 2016-2017 Audi Q5, 2016-2017 Audi Q5, 2016-2016 Audi S4, 2016-2016 Audi S4, 2016-2016 Audi S4, 2016-2016 Audi S4, 2016-2016 Audi S5, 2016-2016 Audi S5, 2016-2016 Audi SQ5, 2016-2016 Audi SQ5, 2015-2015 Audi A7 Quattro, 2015-2015 Audi A7 Quattro, 2014-2016 Audi S5, 2014-2016 Audi S5, 2014-2016 Audi SQ5
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi S4
Item LocatedUnited States
Quantity1
Part interchange
V15-99-2081, 06E121111A, 06E121111E, 6E121111A, 6E121111E, TH728185J, 06E121111AD, 06E121111AL, 
...View more
item #1001QNG5
Note
With seal
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ÜRO Parts 078121121J Engine Coolant Thermostat Housing
ÜRO PartsPart # 078121121J
ÜRO Parts 078121121J Engine Coolant Thermostat Housing
52 Reviews
$142.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2001-2001 Audi A6, 2001-2001 Audi A6 Quattro, 2001-2001 Audi A6 Quattro, 2001-2001 Volkswagen Passat, 2000-2002 Audi S4, 2000-2000 Audi A6 Quattro, 2000-2000 Audi A6 Quattro, 1998-2000 Volkswagen Passat, 1997-2001 Audi A4, 1997-2001 Audi A4 Quattro, 1996-1998 Audi Cabriolet, 1996-1996 Audi A4, 1996-1996 Audi A4 Quattro, 1995-2000 Audi A6, 1995-1999 Audi A6 Quattro, 1995-1995 Audi 90, 1995-1995 Audi 90 Quattro, 1995-1995 Audi Cabriolet
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Vehicle: Audi S4
Item LocatedUnited States
Quantity1
ColorSilver
Part interchange
078121121J, 078121121J, 078121121H, 078121121F, 078121121D, 143-0709, URO-009859
item #1000ZT5K
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ÜRO Parts 074121121B Engine Coolant Thermostat Housing
ÜRO PartsPart # 074121121B
ÜRO Parts 074121121B Engine Coolant Thermostat Housing
52 Reviews
$16.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 1997-1997 Volkswagen EuroVan, 1995-1996 Audi S6, 1992-1996 Volkswagen EuroVan, 1992-1994 Audi S4
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Vehicle: Audi S4
Item LocatedUnited States
Quantity1
Part interchange
074121121B, 074121121B, 147-0060, 902-983, CH-9983, V10-9709, URO-008046
item #1000ZSZX
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ÜRO Parts 06E121111AL Engine Coolant Thermostat / Water Inlet Assembly
ÜRO PartsPart # 06E121111AL
ÜRO Parts 06E121111AL Engine Coolant Thermostat / Water Inlet Assembly
52 Reviews
$49.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2015-2016 Porsche Cayenne, 2015-2016 Porsche Panamera, 2015-2015 Audi A7 Quattro, 2015-2015 Audi A7 Quattro, 2015-2015 Volkswagen Touareg, 2014-2015 Volkswagen Touareg, 2014-2014 Volkswagen Touareg, 2014-2014 Volkswagen Touareg, 2014-2014 Volkswagen Touareg, 2014-2014 Volkswagen Touareg, 2013-2016 Audi S5, 2013-2015 Audi A6 Quattro, 2013-2015 Audi A6 Quattro, 2013-2015 Volkswagen Touareg, 2013-2015 Volkswagen Touareg, 2013-2015 Volkswagen Touareg, 2013-2015 Volkswagen Touareg, 2013-2015 Volkswagen Touareg, 2013-2015 Volkswagen Touareg, 2013-2015 Volkswagen Touareg
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi S4
Item LocatedUnited States
Quantity1
ColorBlack
Part interchange
06E121111AL, 06E121111AL, 06E121111E, 06E121111T, 06E121111S, 06E121111P, 06E121111A, 06E121111AD, 
...View more
item #1000ZT4N
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Vemo V15-99-1985-1 Engine Coolant Thermostat
VemoPart # V15-99-1985-1
Vemo V15-99-1985-1 Engine Coolant Thermostat
57 Reviews
$19.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 1997-1997 Volkswagen EuroVan, 1996-1997 Audi S6, 1995-1996 Volkswagen EuroVan, 1995-1995 Audi S6, 1995-1995 Volkswagen EuroVan, 1993-1993 Volkswagen EuroVan, 1993-1993 Volkswagen EuroVan, 1993-1993 Volkswagen EuroVan, 1992-1994 Audi S4, 1991-1992 Audi 80, 1990-1992 Audi 80 Quattro, 1990-1991 Audi 100, 1990-1991 Audi 100 Quattro, 1990-1991 Audi 200, 1990-1991 Audi 200 Quattro, 1990-1991 Audi 90, 1990-1991 Audi 90 Quattro, 1990-1991 Audi Coupe Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi S4
Item LocatedUnited States
Quantity1
Part interchange
V15-99-1985-1, 78256S, TX2580D, TX2587D, 5302687, 30487, 075121113D, 075121113E, 
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item #1001QLTU
Note
With seal
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Beck/Arnley 143-0664 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0664
Beck/Arnley 143-0664 Engine Coolant Thermostat
52 Reviews
$30.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2001-2002 Volkswagen EuroVan, 1999-2000 Volkswagen EuroVan, 1997-1997 Volkswagen EuroVan, 1995-1997 Volkswagen Golf, 1995-1996 Audi S6, 1994-2004 Volkswagen Jetta, 1993-1997 Volkswagen Passat, 1993-1996 Volkswagen EuroVan, 1993-1995 Volkswagen Corrado, 1992-1994 Audi S4, 1992-1992 Volkswagen Corrado, 1991-1992 Audi 80, 1990-1991 Audi Coupe Quattro, 1989-1991 Audi 100, 1989-1991 Audi 200, 1989-1991 Audi 90, 1988-1992 Audi 80 Quattro, 1988-1991 Audi 90 Quattro, 1988-1988 Audi 90, 1987-1988 Audi 5000
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Vehicle: Audi S4
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0664
item #1000XL7C
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Beck/Arnley 143-0718 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0718
Beck/Arnley 143-0718 Engine Coolant Thermostat
52 Reviews
$36.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2001-2002 Volkswagen EuroVan, 1999-2000 Volkswagen EuroVan, 1997-1997 Volkswagen EuroVan, 1995-1997 Volkswagen Golf, 1995-1996 Audi S6, 1994-1997 Volkswagen Jetta, 1993-1997 Volkswagen Passat, 1993-1996 Volkswagen EuroVan, 1993-1995 Volkswagen Corrado, 1992-1994 Audi S4, 1992-1992 Volkswagen Corrado, 1991-1992 Audi 80, 1990-1991 Audi Coupe Quattro, 1989-1991 Audi 100, 1989-1991 Audi 200, 1989-1991 Audi 90, 1988-1992 Audi 80 Quattro, 1988-1991 Audi 90 Quattro, 1988-1988 Audi 90, 1987-1988 Audi 5000
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi S4
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0718
item #1000XDAE
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Vemo V15-99-1990 Engine Coolant Thermostat
VemoPart # V15-99-1990
Vemo V15-99-1990 Engine Coolant Thermostat
57 Reviews
$32.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2008-2008 Jaguar S-Type, 2008-2008 Jaguar S-Type, 2007-2009 Jaguar XK, 2007-2009 Jaguar XKR, 2007-2007 Jaguar S-Type, 2006-2009 Jaguar XJR, 2006-2006 Jaguar S-Type, 2006-2006 Jaguar XJ8, 2003-2005 Audi Allroad Quattro, 2001-2002 Audi Allroad Quattro, 2001-2001 Volkswagen Passat, 2001-2001 Volkswagen Passat, 2001-2001 Volkswagen Passat, 2001-2001 Volkswagen Passat, 2000-2004 Audi A6 Quattro, 2000-2002 Audi S4, 1999-1999 Audi A4, 1999-1999 Audi A4 Quattro, 1999-1999 Audi A6, 1999-1999 Audi A6 Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi S4
Item LocatedUnited States
Quantity1
Part interchange
V15-99-1990, TX3087D, 78410S, 5305987, 30487, 067121113, 078121113D, 25121113F, 
...View more
item #1001QPCT
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Beck/Arnley 143-0709 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0709
Beck/Arnley 143-0709 Engine Coolant Thermostat
52 Reviews
$32.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2005-2006 Audi A8 Quattro, 2004-2009 Audi S4, 2004-2007 Volkswagen Touareg, 2004-2006 Volkswagen Phaeton, 2003-2005 Audi Allroad Quattro, 2003-2004 Audi RS6, 2002-2006 Audi A6 Quattro, 2002-2004 Audi A6 Quattro, 2002-2003 Audi S6, 2001-2003 Audi S8, 2001-2002 Audi Allroad Quattro, 2000-2002 Audi S4, 2000-2001 Audi A4, 1999-1999 Volkswagen Passat, 1999-1999 Volkswagen Passat, 1998-2004 Volkswagen Jetta, 1998-1999 Volkswagen Golf, 1998-1998 Volkswagen Passat, 1997-2004 Audi A8 Quattro, 1997-2001 Audi A4 Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi S4
Item LocatedUnited States
Quantity1
Part interchange
143-0709
item #1000XG5E
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Beck/Arnley 143-0703 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0703
Beck/Arnley 143-0703 Engine Coolant Thermostat
52 Reviews
$31.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2001-2002 Volkswagen EuroVan, 1999-2000 Volkswagen EuroVan, 1997-1997 Volkswagen EuroVan, 1995-1997 Volkswagen Golf, 1995-1996 Audi S6, 1994-2004 Volkswagen Jetta, 1993-1997 Volkswagen Passat, 1993-1996 Volkswagen EuroVan, 1993-1995 Volkswagen Corrado, 1992-1994 Audi S4, 1992-1992 Volkswagen Corrado, 1991-1992 Audi 80, 1990-1991 Audi Coupe Quattro, 1989-1991 Audi 100, 1989-1991 Audi 200, 1989-1991 Audi 90, 1988-1992 Audi 80 Quattro, 1988-1991 Audi 90 Quattro, 1988-1988 Audi 90, 1987-1988 Audi 5000 Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi S4
Item LocatedUnited States
Quantity1
Part interchange
143-0703
item #1000XECR
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A-Premium APTHA0292 Engine Coolant Thermostat Housing Assembly
A-Premium®Part # APTHA0292
A-Premium APTHA0292 Engine Coolant Thermostat Housing Assembly
4.693 Reviews
$113.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits 2023 - 2024 Porsche Cayenne, 2023 - 2023 Porsche Cayenne, 2022 - 2024 Audi A6 allroad, 2022 - 2024 Audi A6 Quattro, 2022 - 2024 Audi A7 Sportback, 2022 - 2024 Audi RS5, 2022 - 2024 Audi RS5 Sportback, 2022 - 2024 Audi S6, 2022 - 2024 Audi S7 Sportback, 2021 - 2024 Audi Q7, 2021 - 2024 Audi S5, 2021 - 2024 Audi SQ5 Sportback, 2021 - 2022 Porsche Cayenne, 2021 - 2022 Porsche Cayenne, 2021 - 2021 Audi A6 allroad, 2021 - 2021 Audi A6 Quattro, 2021 - 2021 Audi A7 Sportback, 2021 - 2021 Audi RS5, 2021 - 2021 Audi RS5 Sportback, 2021 - 2021 Audi S6
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi S4
Item LocatedUnited States
Quantity1
ColorSilver, Black
ConditionNew
item #101569RN
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Engine Coolant Thermostat - Mahle TI 306 85
MahlePart # TI 306 85
Engine Coolant Thermostat - Mahle TI 306 85
51 Reviews
$47.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2017-2018 Porsche Cayenne, 2017-2017 Audi Q5, 2017-2017 Audi S5, 2017-2017 Audi SQ5, 2016-2017 Audi Q5, 2016-2017 Audi Q5, 2015-2018 Porsche Cayenne, 2015-2016 Audi S4, 2015-2016 Audi S4, 2015-2016 Audi S4, 2015-2016 Audi S4, 2015-2016 Audi S5, 2015-2016 Audi S5, 2015-2015 Audi A6 Quattro, 2015-2015 Audi A6 Quattro, 2015-2015 Audi A7 Quattro, 2015-2015 Audi A7 Quattro, 2015-2015 Audi Q5, 2015-2015 Audi Q5, 2015-2015 Audi Q7
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi S4
Item LocatedUnited States
Quantity1
Part interchange
TI 306 85, 34839, 958 106 032 01, 958 106 032 02, 49688, 758-185, TI30685, 06E 121 111 AL
item #1000XR44
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Engine Coolant Thermostat - Mahle TX 30 87D
MahlePart # TX 30 87D
Engine Coolant Thermostat - Mahle TX 30 87D
51 Reviews
$28.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2003-2005 Audi Allroad Quattro, 2001-2002 Audi Allroad Quattro, 2000-2005 Volkswagen Passat, 2000-2004 Audi A6 Quattro, 2000-2002 Audi S4, 2000-2001 Audi A4, 2000-2001 Audi A4 Quattro, 2000-2001 Audi A6, 2000-2001 Audi A6 Quattro, 1998-1999 Volkswagen Passat, 1997-1999 Audi A4, 1997-1999 Audi A4 Quattro, 1996-1996 Audi A4, 1996-1996 Audi A4 Quattro, 1995-1999 Audi A6, 1995-1999 Audi A6 Quattro, 1994-1998 Audi Cabriolet, 1993-1994 Audi 90, 1993-1994 Audi 90 Quattro, 1992-1994 Audi 100
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi S4
Item LocatedUnited States
Quantity1
Part interchange
TX 30 87D, 4236.88D, 33975, 48049, TX3087D, 304-192, 078 121 113 F, 2.145.87.312
item #1000XRPC
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Engine Coolant Thermostat - Mahle TX 25 87D
MahlePart # TX 25 87D
Engine Coolant Thermostat - Mahle TX 25 87D
51 Reviews
$30.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 1997-1997 Volkswagen EuroVan, 1995-1997 Audi S6, 1992-1996 Volkswagen EuroVan, 1992-1994 Audi S4, 1992-1994 Volkswagen Transporter, 1991-1992 Audi 80, 1990-1991 Audi Coupe Quattro, 1989-1991 Audi 100, 1989-1991 Audi 100 Quattro, 1989-1991 Audi 200, 1989-1991 Audi 200 Quattro, 1989-1991 Audi 90, 1988-1992 Audi 80 Quattro, 1988-1992 Audi 90 Quattro, 1988-1988 Audi 90, 1987-1988 Audi 5000 Quattro, 1987-1987 Audi 5000, 1986-1988 Volkswagen Quantum, 1986-1986 Audi 5000, 1985-1986 Volvo 740
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi S4
Item LocatedUnited States
Quantity1
Part interchange
TX 25 87D, 33518, 13588, TX2587D, 304-192, 069 121 113, 3273728, 2.114.87.312
item #1000XLZ8
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Engine Coolant Thermostat - Mahle TX 30 71D
MahlePart # TX 30 71D
Engine Coolant Thermostat - Mahle TX 30 71D
51 Reviews
$32.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2003-2005 Audi Allroad Quattro, 2001-2002 Audi Allroad Quattro, 2000-2004 Audi A6 Quattro, 2000-2002 Audi S4, 2000-2001 Audi A6 Quattro, 1998-2005 Volkswagen Passat, 1997-2001 Audi A4, 1997-2001 Audi A4 Quattro, 1996-1996 Audi A4, 1996-1996 Audi A4 Quattro, 1995-2001 Audi A6, 1995-1999 Audi A6 Quattro, 1994-1998 Audi Cabriolet, 1993-1994 Audi 90, 1993-1994 Audi 90 Quattro, 1992-1994 Audi 100, 1992-1994 Audi 100 Quattro, 1990-1994 Audi V8 Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi S4
Item LocatedUnited States
Quantity1
Part interchange
TX 30 71D, 4235.71D, TX3071D, 2.145.71.312
item #1000XSE0
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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