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Audi Thermostat

116 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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Vaico V10-0278 Engine Coolant Thermostat HousingVaico V10-0278 Engine Coolant Thermostat Housing
VaicoPart # V10-0278
Vaico V10-0278 Engine Coolant Thermostat Housing
4.17 Reviews
$14.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2000-2002 Audi TT Quattro, 2000-2004 Audi TT, 2003-2006 Audi TT Quattro, 2005-2006 Audi TT, 1998-1998 Volkswagen Beetle, 1999-1999 Volkswagen Beetle, 1999-1999 Volkswagen Beetle, 1999-1999 Volkswagen Beetle, 1999-1999 Volkswagen Golf, 1999-2005 Volkswagen Jetta, 1999-2005 Volkswagen Jetta, 1999-2006 Volkswagen Golf, 1999-2006 Volkswagen Golf, 2000-2000 Volkswagen Golf, 2000-2000 Volkswagen Golf, 2000-2002 Volkswagen Beetle, 2000-2003 Volkswagen Beetle, 2000-2004 Volkswagen Beetle, 2000-2005 Volkswagen Beetle, 2000-2005 Volkswagen Jetta
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi
Item LocatedUnited States
Quantity1
Part interchange
V10-0278, 23856, 52812, 06A121121C, 6A121121C, 6A121121F, 038121121D, 06A121121F, 
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item #10010AAW
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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
Edit ZIP code
3-year warranty
90 days free return
Fits 1992-1994 Audi S4, 1995-1995 Audi S6, 1993-1993 Volkswagen EuroVan, 1993-1993 Volkswagen EuroVan, 1993-1993 Volkswagen EuroVan, 1995-1995 Volkswagen EuroVan
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Vehicle: Audi
Item LocatedUnited States
Quantity1
Part interchange
V10-9709, 74121121, 074121121, 074121121B, 74121121B, 902983, 1470060
item #100106Z0
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Vaico V10-0280 Engine Coolant Thermostat Housing
VaicoPart # V10-0280
Vaico V10-0280 Engine Coolant Thermostat Housing
4.17 Reviews
$10.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1990-1990 Audi 80, 1990-1991 Volkswagen Corrado, 1990-1992 Volkswagen Golf, 1990-1992 Volkswagen Golf, 1990-1992 Volkswagen Golf, 1990-1992 Volkswagen Jetta, 1990-1992 Volkswagen Jetta, 1990-1992 Volkswagen Jetta, 1990-1992 Volkswagen Jetta, 1990-1992 Volkswagen Passat, 1990-1993 Volkswagen Cabriolet, 1992-1992 Volkswagen Corrado, 1992-1992 Volkswagen Passat, 1993-1993 Volkswagen Passat
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi
Item LocatedUnited States
Quantity1
Part interchange
V10-0280, 34171, 50062, 055121121, 055121121C, 55121011A, 55121121A, 55121121F, 
...View more
item #10010AWW
Note
from water pipe to water pump
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Vaico V10-0283 Engine Coolant Thermostat Housing, Cylinder Head
VaicoPart # V10-0283
Vaico V10-0283 Engine Coolant Thermostat Housing, Cylinder Head
4.17 Reviews
$12.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1997-1997 Audi A4, 1997-1998 Audi A4 Quattro, 1998-1999 Audi A4, 1999-2000 Audi A4 Quattro, 1999-2000 Audi A4 Quattro, 2000-2000 Audi A4, 1998-1998 Volkswagen Passat, 1999-2000 Volkswagen Passat
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi
Item LocatedUnited States
Quantity1
Installation PositionCylinder Head
Part interchange
V10-0283, 23346, 50044, 030121121, 055121121E, 30121121B, 030121121B, 30121121, 
...View more
item #1001080S
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Vaico V10-8198 Engine Coolant Thermostat Housing
VaicoPart # V10-8198
Vaico V10-8198 Engine Coolant Thermostat Housing
4.17 Reviews
$16.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2001-2001 Audi A4, 2001-2001 Audi A4 Quattro, 2001-2001 Audi A4 Quattro, 2000-2005 Volkswagen Passat, 2003-2005 Volkswagen Passat, 2004-2005 Volkswagen Passat
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi
Item LocatedUnited States
Quantity1
MaterialPlastic
Part interchange
V10-8198, 85134, 18244, 50069, 6B121121L, 6B121121, 06B121121L, 06B121121, 
...View more
item #1001098N
Show less
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 5 left
Edit ZIP code
3-year warranty
90 days free return
Fits 2009-2009 Audi A6 Quattro, 2010-2011 Audi A6 Quattro, 2010-2011 Audi A6 Quattro, 2010-2011 Audi S5, 2010-2013 Audi S4, 2011-2015 Audi Q7, 2011-2015 Audi Q7, 2011-2015 Audi Q7, 2012-2012 Audi S5, 2012-2014 Audi A6 Quattro, 2012-2014 Audi A7 Quattro, 2012-2015 Audi A6 Quattro, 2012-2015 Audi A6 Quattro, 2013-2013 Audi S5, 2013-2014 Audi A8 Quattro, 2013-2014 Audi A8 Quattro, 2013-2017 Audi Q5, 2013-2017 Audi Q5, 2014-2015 Audi S4, 2014-2015 Audi S4
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi
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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Vemo V15-99-1894 Engine Coolant Thermostat
VemoPart # V15-99-1894
Vemo V15-99-1894 Engine Coolant Thermostat
57 Reviews
$21.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1990-1990 Audi 80, 1990-1991 Volkswagen Corrado, 1990-1992 Volkswagen Golf, 1990-1992 Volkswagen Golf, 1990-1992 Volkswagen Golf, 1990-1992 Volkswagen Jetta, 1990-1992 Volkswagen Jetta, 1990-1992 Volkswagen Jetta, 1990-1992 Volkswagen Jetta, 1990-1992 Volkswagen Passat, 1990-1993 Volkswagen Cabriolet, 1990-1993 Volkswagen Fox, 1992-1992 Volkswagen Corrado, 1992-1992 Volkswagen Passat, 1993-1993 Volkswagen Golf, 1993-1993 Volkswagen Jetta, 1993-1993 Volkswagen Passat, 1994-1994 Volkswagen Golf, 1994-1994 Volkswagen Jetta, 1995-1995 Volkswagen Cabrio
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi
Item LocatedUnited States
Quantity1
Part interchange
V15-99-1894, TX1387D, 78223S, 5307087, 5301887, 5303587, 23487, 068121113D, 
...View more
item #1001QQD9
Note
With seal
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Vemo V15-99-2107 Engine Coolant Thermostat Housing
VemoPart # V15-99-2107
Vemo V15-99-2107 Engine Coolant Thermostat Housing
57 Reviews
$536.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2015-2017 Audi A3, 2015-2017 Audi A3 Quattro, 2015-2017 Audi S3, 2016-2016 Audi A6 Quattro, 2016-2017 Audi A6, 2016-2017 Audi TT Quattro, 2016-2017 Audi TTS Quattro, 2017-2017 Audi A4, 2017-2017 Audi A4 Quattro, 2017-2017 Audi A4 allroad, 2017-2017 Audi A6 Quattro, 2017-2017 Audi Q7, 2015-2015 Volkswagen Golf SportWagen, 2015-2017 Volkswagen Golf R, 2016-2017 Volkswagen GTI, 2016-2017 Volkswagen Golf, 2016-2017 Volkswagen Golf SportWagen, 2017-2017 Volkswagen Golf Alltrack
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi
Item LocatedUnited States
Quantity1
Part interchange
V15-99-2107, 06K121605, 06L121111P, 06L121012A, 06L121131, 06L121012H, 06L121111J, 06L121111L, 
...View more
item #1001QN05
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Vemo V15-99-2116 Engine Coolant Thermostat Housing
VemoPart # V15-99-2116
Vemo V15-99-2116 Engine Coolant Thermostat Housing
57 Reviews
$154.99
Low stock: Only 2 left
Edit ZIP code
3-year warranty
90 days free return
Fits 2016-2016 Audi A3 Sportback e-tron, 2016-2016 Audi A3 Sportback e-tron, 2016-2016 Audi A3 Sportback e-tron, 2017-2017 Audi A3 Sportback e-tron, 2013-2014 Volkswagen Jetta, 2013-2014 Volkswagen Jetta, 2013-2014 Volkswagen Jetta, 2014-2014 Volkswagen Jetta, 2015-2015 Volkswagen Jetta, 2016-2016 Volkswagen Jetta, 2016-2016 Volkswagen Jetta, 2016-2016 Volkswagen Jetta, 2017-2017 Volkswagen Jetta, 2021-2021 Volkswagen Golf, 2021-2021 Volkswagen Jetta, 2021-2021 Volkswagen Jetta, 2021-2021 Volkswagen Jetta, 2021-2021 Volkswagen Jetta, 2021-2021 Volkswagen Jetta, 2021-2021 Volkswagen Jetta
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi
Item LocatedUnited States
Quantity1
Part interchange
V15-99-2116, 04E121116C
item #1001QQ53
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Vemo V15-99-2110 Engine Coolant Thermostat Housing
VemoPart # V15-99-2110
Vemo V15-99-2110 Engine Coolant Thermostat Housing
57 Reviews
$193.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2015-2016 Audi A3, 2015-2016 Audi A3, 2015-2016 Audi A3, 2015-2015 Volkswagen Beetle, 2015-2015 Volkswagen Golf, 2015-2015 Volkswagen Golf, 2015-2015 Volkswagen Golf, 2015-2015 Volkswagen Golf SportWagen, 2015-2015 Volkswagen Golf SportWagen, 2015-2015 Volkswagen Golf SportWagen, 2015-2015 Volkswagen Jetta, 2015-2015 Volkswagen Jetta, 2015-2015 Volkswagen Jetta, 2015-2015 Volkswagen Passat, 2015-2015 Volkswagen Passat
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi
Item LocatedUnited States
Quantity1
Part interchange
V15-99-2110, 04L121026J, 04L121026AH, 04L121113D, ­04L121026J, 4L121026F, 04L121026AE, 04L121026E, 
...View more
item #1001QS0P
Note
With thermostat, Pre-Assembled
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Beck/Arnley 143-0149 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0149
Beck/Arnley 143-0149 Engine Coolant Thermostat
51 Reviews
$19.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1964-1968 Alfa Romeo Giulia Sprint, 1997-2002 Audi A4, 1960-1966 Austin Mini, 1962-1962 Austin Mini Cooper, 1963-1963 Austin Mini Cooper, 1964-1964 Austin Mini Cooper, 1965-1965 Austin Mini Cooper, 1966-1967 Austin Mini Cooper, 1968-1969 Austin Mini Cooper, 1968-1970 Austin America, 1973-1975 Austin Marina, 1956-1959 Austin Healey 100-6, 1958-1961 Austin Healey Sprite, 1959-1967 Austin Healey 3000, 1962-1962 Austin Healey Sprite, 1963-1966 Austin Healey Sprite, 1967-1967 Austin Healey Sprite, 1968-1969 Austin Healey Sprite, 1988-1989 Eagle Premier, 1967-1969 Fiat 124
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0149
item #1000XG3Z
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Vemo V15-99-2067 Engine Coolant Thermostat Kit
VemoPart # V15-99-2067
Vemo V15-99-2067 Engine Coolant Thermostat Kit
57 Reviews
$101.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2005-2005 Audi A4 Quattro, 2005-2005 Audi A4 Quattro, 2005-2005 Audi A4 Quattro, 2005-2005 Audi A4 Quattro, 2005-2005 Audi A4 Quattro, 2005-2005 Audi A6 Quattro, 2005-2008 Audi A4 Quattro, 2005-2008 Audi A4 Quattro, 2006-2007 Audi A4, 2006-2008 Audi A6, 2006-2008 Audi A6 Quattro, 2006-2008 Audi A6 Quattro, 2007-2009 Audi A4 Quattro, 2008-2008 Audi A4, 2008-2009 Audi A5 Quattro, 2009-2010 Audi Q5, 2009-2012 Audi Q5, 2009-2012 Audi Q5, 2010-2010 Audi A5 Quattro, 2010-2010 Audi A5 Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi
Item LocatedUnited States
Quantity1
Part interchange
V15-99-2067, 50688, 862021688, 1601479182, TH698988, 06E121111M, 6E121111D, 6E121111G, 
...View more
item #1000X6Z7
Show less
Vemo V15-99-2046 Engine Coolant Thermostat Kit
VemoPart # V15-99-2046
Vemo V15-99-2046 Engine Coolant Thermostat Kit
57 Reviews
$65.99
Low stock: Only 3 left
Edit ZIP code
3-year warranty
90 days free return
Fits 2010-2013 Audi A3, 2009-2014 Volkswagen Jetta, 2010-2010 Volkswagen Golf, 2010-2010 Volkswagen Jetta, 2011-2014 Volkswagen Golf, 2012-2014 Volkswagen Jetta, 2013-2014 Volkswagen Beetle
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi
Item LocatedUnited States
Quantity1
Part interchange
V15-99-2046, TI3387, 9025907, 03L121111AC, 03L121111AM, 03L121111M, 3L121111AC, 3L121111M
item #1000XCYZ
Note
Without gasket/seal, With thermostat
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Vemo V15-99-2069 Engine Coolant Thermostat
VemoPart # V15-99-2069
Vemo V15-99-2069 Engine Coolant Thermostat
57 Reviews
$42.99
Low stock: Only 2 left
Edit ZIP code
3-year warranty
90 days free return
Fits 2009-2009 Audi A3 Quattro, 2009-2012 Audi A4 Quattro, 2009-2013 Audi A3, 2009-2014 Audi A4, 2009-2014 Audi A4 Quattro, 2010-2010 Audi A5, 2010-2010 Audi A5 Quattro, 2010-2011 Audi A3 Quattro, 2011-2012 Audi Q5, 2011-2012 Audi Q5, 2011-2014 Audi A5, 2011-2014 Audi A5 Quattro, 2011-2014 Audi A5 Quattro, 2012-2012 Audi A6, 2012-2013 Audi A3 Quattro, 2013-2014 Audi A6, 2013-2014 Audi A6, 2013-2015 Audi A6 Quattro, 2013-2015 Audi A6 Quattro, 2013-2016 Audi allroad
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi
Item LocatedUnited States
Quantity1
Part interchange
V15-99-2069, 78742, 862031695, TX11795D, TX12395D, 06J121113, 6J121113, 6J121113A, 
...View more
item #1001QQ5S
Note
With seal
Show less
Vemo V15-99-0004 Engine Coolant Thermostat Housing
VemoPart # V15-99-0004
Vemo V15-99-0004 Engine Coolant Thermostat Housing
57 Reviews
$142.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2001-2001 Audi A6, 2001-2001 Audi A6 Quattro, 2001-2001 Audi A6 Quattro, 2001-2001 Audi A6 Quattro, 2001-2002 Audi Allroad Quattro, 2002-2004 Audi A6 Quattro, 2003-2005 Audi Allroad Quattro, 2001-2001 Volkswagen Passat, 2001-2001 Volkswagen Passat, 2001-2001 Volkswagen Passat, 2001-2001 Volkswagen Passat, 2002-2002 Volkswagen Passat, 2002-2005 Volkswagen Passat, 2002-2005 Volkswagen Passat, 2002-2005 Volkswagen Passat, 2003-2004 Volkswagen Passat, 2005-2005 Volkswagen Passat
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi
Item LocatedUnited States
Quantity1
MaterialPlastic
item #1001QPYW
Note
Without thermostat
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Vemo V15-99-2043-1 Engine Coolant Thermostat Housing
VemoPart # V15-99-2043-1
Vemo V15-99-2043-1 Engine Coolant Thermostat Housing
57 Reviews
$67.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2015-2015 Audi Q3, 2016-2016 Audi Q3, 2017-2017 Audi Q3 Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi
Item LocatedUnited States
Quantity1
Part interchange
V15-99-2043-1, 3L121111AE, 03L121111AL, 03L121111AE
item #1001QPE0
Show less
Beck/Arnley 143-0709 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0709
Beck/Arnley 143-0709 Engine Coolant Thermostat
51 Reviews
$32.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1990-1994 Audi V8 Quattro, 1992-1994 Audi 100, 1993-1995 Audi 90, 1993-1995 Audi 90 Quattro, 1994-1998 Audi Cabriolet, 1995-2001 Audi A6, 1995-2001 Audi A6 Quattro, 1996-1996 Audi A4, 1997-1999 Audi A4, 1997-1999 Audi A8, 1997-2001 Audi A4 Quattro, 1997-2004 Audi A8 Quattro, 2000-2001 Audi A4, 2000-2002 Audi S4, 2001-2002 Audi Allroad Quattro, 2001-2003 Audi S8, 2002-2003 Audi S6, 2002-2004 Audi A6 Quattro, 2002-2006 Audi A6 Quattro, 2003-2004 Audi RS6
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi
Item LocatedUnited States
Quantity1
Part interchange
143-0709
item #1000XG5E
Show less
Beck/Arnley 143-0703 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0703
Beck/Arnley 143-0703 Engine Coolant Thermostat
51 Reviews
$31.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1978-1983 Audi 5000, 1980-1981 Audi 4000, 1981-1983 Audi Coupe, 1983-1985 Audi Quattro, 1984-1984 Audi 5000, 1984-1986 Audi Coupe, 1984-1987 Audi 4000 Quattro, 1985-1985 Audi 5000, 1985-1985 Audi 5000, 1987-1987 Audi Coupe, 1987-1988 Audi 5000 Quattro, 1988-1988 Audi 90, 1988-1991 Audi 90 Quattro, 1988-1992 Audi 80 Quattro, 1989-1991 Audi 100, 1989-1991 Audi 200, 1989-1991 Audi 90, 1990-1991 Audi Coupe Quattro, 1991-1992 Audi 80, 1992-1994 Audi S4
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi
Item LocatedUnited States
Quantity1
Part interchange
143-0703
item #1000XECR
Show less
Beck/Arnley 143-0718 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0718
Beck/Arnley 143-0718 Engine Coolant Thermostat
51 Reviews
$36.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1978-1983 Audi 5000, 1981-1983 Audi Coupe, 1983-1985 Audi Quattro, 1984-1984 Audi 5000, 1984-1986 Audi Coupe, 1984-1987 Audi 4000 Quattro, 1985-1985 Audi 5000, 1985-1985 Audi 5000, 1987-1987 Audi Coupe, 1987-1988 Audi 5000, 1988-1988 Audi 90, 1988-1991 Audi 90 Quattro, 1988-1992 Audi 80 Quattro, 1989-1991 Audi 100, 1989-1991 Audi 200, 1989-1991 Audi 90, 1990-1991 Audi Coupe Quattro, 1991-1992 Audi 80, 1992-1994 Audi S4, 1995-1996 Audi S6
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0718
item #1000XDAE
Show less
Beck/Arnley 143-0706 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0706
Beck/Arnley 143-0706 Engine Coolant Thermostat
51 Reviews
$20.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1970-1971 Audi 100 Series, 1970-1972 Audi Super 90, 1972-1973 Audi 100 Series, 1972-1973 Audi 100 Series, 1972-1974 Audi 100 Series, 1973-1974 Audi Fox, 1975-1977 Audi 100 Series, 1975-1979 Audi Fox, 1980-1980 Audi 4000, 1981-1983 Audi 4000, 1982-1983 Audi 4000, 1984-1986 Audi 4000, 1987-1987 Audi 4000, 1988-1988 Audi 90, 1988-1990 Audi 80, 1971-1971 Fiat 128, 1972-1973 Fiat 128, 1973-1973 Fiat 128, 1973-1973 Fiat 128, 1974-1974 Fiat X-1/9
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0706
item #1000XH49
Show less
Page 1 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.