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Volkswagen Jetta Thermostat

78 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 Ford Explorer Volkswagen Jetta Mercedes-Benz 87℃Engine Coolant Thermostat for Ford Explorer Volkswagen Jetta Mercedes-Benz 87℃
A-Premium®Part # APTHE094
Engine Coolant Thermostat for Ford Explorer Volkswagen Jetta Mercedes-Benz 87℃
4.685 Reviews
$17.99
Low stock: Only 3 left
Edit ZIP code
2-year warranty
90 days free return
Fits 1966 - 1967 Mercedes-Benz 200, 1986 - 1991 Volkswagen Transporter, 1987 - 1990 Volvo 780, 2007 - 2010 Ford Explorer Sport Trac, 1976 - 1979 Volvo 265, 1984 - 1985 Renault Fuego, 1990 - 1991 Mercedes-Benz 300CE, 1966 - 1966 Mercedes-Benz 230S, 1982 - 1984 Peugeot 604, 1977 - 1979 Peugeot 604, 1978 - 1982 Porsche 928, 1963 - 1966 Mercedes-Benz 230SL, 1980 - 1982 Volvo 264, 1981 - 1984 Mercedes-Benz L1116, 1990 - 1992 Dodge Monaco, 1976 - 1976 Volvo 262, 1968 - 1972 Mercedes-Benz 280SE, 1992 - 1993 Volkswagen Corrado, 1979 - 1981 Peugeot 604, 1990 - 1993 Mercedes-Benz 300SL
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Vehicle: Volkswagen Jetta
Item LocatedUnited States
Quantity1
ConditionNew
item #1018814Y
Note
Start to Open Temperature: 87℃.
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Engine Coolant Thermostat Housing Assembly for Volkswagen Golf 2010-2014 Passat
A-Premium®Part # APTHA0111
Engine Coolant Thermostat Housing Assembly for Volkswagen Golf 2010-2014 Passat
4.685 Reviews
$17.99
Low stock: Only 1 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2017 - 2018 Audi A4 allroad, 2017 - 2018 Audi A4 Quattro, 2018 - 2018 Audi A5 Quattro, 2018 - 2018 Audi A5 Sportback, 2009 - 2009 Audi TT, 2009 - 2014 Audi TT Quattro, 2006 - 2010 Volkswagen Beetle, 2012 - 2014 Volkswagen Beetle, 2013 - 2013 Volkswagen CC, 2010 - 2014 Volkswagen Golf, 2005 - 2005 Volkswagen Jetta, 2006 - 2006 Volkswagen Jetta, 2007 - 2007 Volkswagen Jetta, 2008 - 2008 Volkswagen Jetta, 2009 - 2010 Volkswagen Jetta, 2011 - 2011 Volkswagen Jetta, 2012 - 2012 Volkswagen Jetta, 2013 - 2013 Volkswagen Jetta, 2014 - 2014 Volkswagen Jetta, 2011 - 2011 Volkswagen Jetta
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Volkswagen Jetta
Item LocatedUnited States
Quantity1
Part interchange
V15992053, 1K0121113A, 4E0121113
item #1005EYA1
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A-Premium APTHE015 Engine Coolant Thermostat
A-Premium®Part # APTHE015
A-Premium APTHE015 Engine Coolant Thermostat
4.685 Reviews
$21.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2009 - 2013 Audi A3, 2009 - 2013 Audi A3 Quattro, 2009 - 2014 Audi A4, 2013 - 2013 Audi A4 allroad, 2009 - 2013 Audi A4 Quattro, 2010 - 2011 Audi A5, 2010 - 2011 Audi A5 Quattro, 2017 - 2017 Audi A5 Quattro, 2015 - 2015 Audi A6, 2013 - 2013 Audi A6 Quattro, 2015 - 2015 Audi A6 Quattro, 2013 - 2016 Audi allroad, 2011 - 2012 Audi Q5, 2011 - 2011 Audi TT Quattro, 2012 - 2014 Audi TT Quattro, 2009 - 2012 Volkswagen CC, 2014 - 2016 Volkswagen Eos, 2013 - 2013 Volkswagen Jetta, 2009 - 2010 Volkswagen Passat, 2009 - 2011 Volkswagen Passat CC
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Volkswagen Jetta
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1005V0YZ
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A-Premium APTHE011 Engine Coolant Thermostat
A-Premium®Part # APTHE011
A-Premium APTHE011 Engine Coolant Thermostat
4.685 Reviews
$30.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2010 - 2011 Audi A3, 2008 - 2013 Audi A3, 2008 - 2008 Audi A3, 2009 - 2013 Audi A3, 2009 - 2013 Audi A3 Quattro, 2008 - 2010 Audi A4, 2009 - 2012 Audi A4, 2015 - 2016 Audi A4, 2014 - 2016 Audi A4 allroad, 2009 - 2013 Audi A4 Quattro, 2014 - 2016 Audi A4 Quattro, 2012 - 2014 Audi A5, 2012 - 2016 Audi A5 Quattro, 2017 - 2017 Audi A5 Quattro, 2012 - 2014 Audi A6, 2015 - 2015 Audi A6, 2013 - 2013 Audi A6 Quattro, 2014 - 2015 Audi A6 Quattro, 2013 - 2016 Audi allroad, 2015 - 2018 Audi Q3
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Volkswagen Jetta
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1005V2E3
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A-Premium APTHE004 Engine Coolant Thermostat
A-Premium®Part # APTHE004
A-Premium APTHE004 Engine Coolant Thermostat
4.685 Reviews
$31.99
Edit ZIP code
2-year warranty
90 days free return
Fits 1980 - 1982 AMC Concord, 1981 - 1983 AMC Eagle, 1977 - 1977 AMC Gremlin, 1980 - 1982 AMC Spirit, 1979 - 1979 AMC Spirit, 2013 - 2021 Blue Bird Vision School Bus, 1981 - 1986 Chevrolet Chevette, 1982 - 1982 Datsun 720, 1978 - 1978 Dodge D100, 1979 - 1979 Dodge D100, 1978 - 1978 Dodge D150, 1979 - 1980 Dodge D150, 1978 - 1978 Dodge D200, 1980 - 1980 Dodge D200, 1983 - 1985 Dodge Power Ram 50, 1983 - 1985 Dodge Ram 50, 1978 - 1978 Dodge W150, 1979 - 1979 Dodge W150, 1978 - 1978 Dodge W200, 1979 - 1979 Dodge W200
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Volkswagen Jetta
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1005V2C8
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A-Premium APTHE005 Engine Coolant Thermostat
A-Premium®Part # APTHE005
A-Premium APTHE005 Engine Coolant Thermostat
4.685 Reviews
$20.99
Edit ZIP code
2-year warranty
90 days free return
Fits 1980 - 1982 AMC Concord, 1981 - 1983 AMC Eagle, 1977 - 1977 AMC Gremlin, 1980 - 1982 AMC Spirit, 1979 - 1979 AMC Spirit, 2013 - 2021 Blue Bird Vision School Bus, 1982 - 1982 Isuzu I-Mark, 1984 - 1984 Isuzu I-Mark, 1985 - 1987 Jaguar Vanden Plas, 1978 - 1978 Jaguar XJ6, 1983 - 1987 Jaguar XJ6, 1971 - 1974 Jaguar XKE, 1980 - 1983 Jeep CJ5, 1980 - 1983 Jeep CJ7, 1980 - 1983 Jeep DJ5, 1981 - 1983 Jeep Scrambler, 2002 - 2002 Lincoln Blackwood, 2006 - 2008 Lincoln Mark LT, 1998 - 2014 Lincoln Navigator, 1991 - 2011 Lincoln Town Car
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Volkswagen Jetta
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1005V0CQ
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A-Premium APTHE069 Engine Coolant Thermostat
A-Premium®Part # APTHE069
A-Premium APTHE069 Engine Coolant Thermostat
4.685 Reviews
$22.99
Low stock: Only 5 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2013 - 2013 Audi A3, 2016 - 2018 Audi A3 Sportback e-tron, 2021 - 2021 Volkswagen Golf, 2019 - 2020 Volkswagen Golf, 2019 - 2019 Volkswagen Golf SportWagen, 2013 - 2020 Volkswagen Jetta
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Vehicle: Volkswagen Jetta
Item LocatedUnited States
Quantity1
ConditionNew
item #1005V3EG
Note
This item comes with thermostat insert and seal.
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A-Premium APTHA0263 Engine Coolant Thermostat Housing Assembly
A-Premium®Part # APTHA0263
A-Premium APTHA0263 Engine Coolant Thermostat Housing Assembly
4.685 Reviews
$49.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2006 - 2010 Volkswagen Beetle, 2012 - 2019 Volkswagen Beetle, 2010 - 2014 Volkswagen Golf, 2005 - 2018 Volkswagen Jetta, 2012 - 2018 Volkswagen Passat, 2006 - 2009 Volkswagen Rabbit
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Vehicle: Volkswagen Jetta
Item LocatedUnited States
Quantity1
ColorBlack
ConditionNew
item #10156DQR
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Thermostat Housing Assembly for VW Golf Jetta 2010-2014 Audi TTS Quattro 2.0L
A-Premium®Part # APTHA0229
Thermostat Housing Assembly for VW Golf Jetta 2010-2014 Audi TTS Quattro 2.0L
4.685 Reviews
$42.99
Low stock: Only 3 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2010 - 2010 Audi TTS Quattro, 2010 - 2010 Volkswagen Bora, 2013 - 2014 Volkswagen Beetle, 2010 - 2014 Volkswagen Golf, 2010 - 2014 Volkswagen Jetta
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Volkswagen Jetta
Item LocatedUnited States
Quantity1
MaterialPlastic
Part interchange
902-5907, 85967, 806189, V15992046, 03L121111AC, 03L121111M, 03L121111AM, 194087
item #10027QLZ
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Thermostat Housing Assembly with Thermostat for Audi A3 Volkswagen Beetle Golf
A-Premium®Part # APTHA0216
Thermostat Housing Assembly with Thermostat for Audi A3 Volkswagen Beetle Golf
4.685 Reviews
$70.99
Low stock: Only 2 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2015 - 2016 Audi A3, 2015 - 2016 Audi A3 Quattro, 2015 - 2015 Volkswagen Beetle, 2015 - 2015 Volkswagen CC, 2015 - 2015 Volkswagen Golf, 2015 - 2015 Volkswagen Golf SportWagen, 2015 - 2015 Volkswagen Jetta, 2015 - 2015 Volkswagen Passat
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Volkswagen Jetta
Item LocatedUnited States
Quantity1
MaterialPlastic
Part interchange
86305, V15992110, 04L121113B, 04L121026F, 04L121026AE, 04L121026AF, 04L121026AH, 04L121026J, 
...View more
item #10027Q1X
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Engine Coolant Thermostat for VW Jetta 05-18 Golf 10-14 Passat Beetle Rabbit 80℃
A-Premium®Part # APTHE066
Engine Coolant Thermostat for VW Jetta 05-18 Golf 10-14 Passat Beetle Rabbit 80℃
4.685 Reviews
$31.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2006 - 2010 Volkswagen Beetle, 2012 - 2019 Volkswagen Beetle, 2010 - 2014 Volkswagen Golf, 2005 - 2018 Volkswagen Jetta, 2012 - 2018 Volkswagen Passat, 2006 - 2009 Volkswagen Rabbit
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Volkswagen Jetta
Item LocatedUnited States
Quantity1
ConditionNew
item #1013DTKL
Note
Start to Open Temperature: 80℃.
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Engine Coolant Thermostat for Audi A3 Sportback e-tron A3 Volkswagen Jetta 1.4L
A-Premium®Part # APTHE070
Engine Coolant Thermostat for Audi A3 Sportback e-tron A3 Volkswagen Jetta 1.4L
4.685 Reviews
$26.99
Low stock: Only 4 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2018 - 2019 Audi A3, 2016 - 2016 Audi A3 Sportback e-tron, 2017 - 2017 Audi A3 Sportback e-tron, 2013 - 2018 Volkswagen Jetta
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Volkswagen Jetta
Item LocatedUnited States
Quantity1
ConditionNew
item #1013DYT2
Note
Start to Open Temperature: 105℃.
Show less
A-Premium APTHE003 Engine Coolant Thermostat
A-Premium®Part # APTHE003
A-Premium APTHE003 Engine Coolant Thermostat
4.685 Reviews
$20.99
Edit ZIP code
2-year warranty
90 days free return
Fits 1980 - 1982 AMC Concord, 1981 - 1983 AMC Eagle, 1977 - 1977 AMC Gremlin, 1980 - 1982 AMC Spirit, 1979 - 1979 AMC Spirit, 2013 - 2021 Blue Bird Vision School Bus, 1981 - 1986 Chevrolet Chevette, 1982 - 1982 Datsun 720, 1978 - 1978 Dodge D100, 1979 - 1979 Dodge D100, 1978 - 1978 Dodge D150, 1979 - 1980 Dodge D150, 1978 - 1978 Dodge D200, 1980 - 1980 Dodge D200, 1983 - 1985 Dodge Power Ram 50, 1983 - 1985 Dodge Ram 50, 1978 - 1978 Dodge W150, 1979 - 1979 Dodge W150, 1978 - 1978 Dodge W200, 1979 - 1979 Dodge W200
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Volkswagen Jetta
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1005V2KW
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Engine Coolant Thermostat for Volkswagen Jetta 13-18 Passat Beetle 1.8L 2.0L
A-Premium®Part # APTHE042
Engine Coolant Thermostat for Volkswagen Jetta 13-18 Passat Beetle 1.8L 2.0L
4.685 Reviews
$37.99
Low stock: Only 3 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2014 - 2017 Volkswagen Beetle, 2013 - 2017 Volkswagen Beetle, 2014 - 2018 Volkswagen Jetta, 2013 - 2013 Volkswagen Jetta, 2014 - 2015 Volkswagen Jetta, 2016 - 2018 Volkswagen Jetta, 2014 - 2017 Volkswagen Passat
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Volkswagen Jetta
Item LocatedUnited States
Quantity1
ConditionNew
item #1013DXUV
Note
Start to Open Temperature: 85℃.
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Engine Coolant Thermostat for Volkswagen Jetta Passat Golf Beetle Audi A4 A3 87℃
A-Premium®Part # APTHE099
Engine Coolant Thermostat for Volkswagen Jetta Passat Golf Beetle Audi A4 A3 87℃
4.685 Reviews
$14.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2008 - 2009 Volkswagen Jetta City, 2008 - 2010 Volkswagen Golf City, 1999 - 2006 Volkswagen Golf, 2007 - 2009 Volkswagen Jetta, 1997 - 2001 Audi A4, 1998 - 2005 Volkswagen Passat, 2009 - 2010 Volkswagen Jetta, 2000 - 2006 Audi TT Quattro, 2010 - 2013 Audi A3, 2010 - 2010 Volkswagen Golf, 2011 - 2011 Volkswagen Jetta, 1993 - 1994 Volkswagen Golf, 1997 - 1997 Volkswagen Golf, 1998 - 2005 Volkswagen Jetta, 2000 - 2006 Audi TT, 1999 - 2005 Volkswagen Beetle, 2010 - 2013 Volkswagen Jetta, 2000 - 2005 Volkswagen Jetta, 1998 - 2006 Volkswagen Beetle, 2011 - 2013 Volkswagen Golf
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Volkswagen Jetta
Item LocatedUnited States
Quantity1
ConditionNew
item #101880H9
Note
Start to Open Temperature: 87℃.
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Thermostat Housing Assembly for VW Jetta Passat Beetle Golf Tiguan Audi A3 A6 Q7
A-Premium®Part # APTHA0152
Thermostat Housing Assembly for VW Jetta Passat Beetle Golf Tiguan Audi A3 A6 Q7
4.685 Reviews
$35.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2008 - 2008 Audi A3, 2008 - 2013 Audi A3, 2009 - 2013 Audi A3 Quattro, 2009 - 2016 Audi A4, 2013 - 2016 Audi A4 allroad, 2009 - 2016 Audi A4 Quattro, 2010 - 2014 Audi A5, 2010 - 2017 Audi A5 Quattro, 2012 - 2015 Audi A6, 2013 - 2015 Audi A6 Quattro, 2013 - 2016 Audi allroad, 2015 - 2018 Audi Q3, 2015 - 2018 Audi Q3 Quattro, 2011 - 2012 Audi Q5, 2013 - 2017 Audi Q5, 2017 - 2017 Audi Q7, 2009 - 2010 Audi TT Quattro, 2011 - 2013 Audi TT Quattro, 2014 - 2014 Audi TT Quattro, 2015 - 2015 Audi TT Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Volkswagen Jetta
Item LocatedUnited States
Quantity1
ColorBlack
item #10027N7L
Note
This item comes with housing and seal.
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Vaico V10-8196 Engine Coolant Thermostat Housing, Upper
VaicoPart # V10-8196
Vaico V10-8196 Engine Coolant Thermostat Housing, Upper
4.17 Reviews
$41.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1992-1992 Volkswagen Corrado, 1993-1993 Volkswagen Passat, 1993-1994 Volkswagen Corrado, 1994-1994 Volkswagen Jetta, 1994-1994 Volkswagen Passat, 1995-1997 Volkswagen Passat, 1995-1998 Volkswagen Golf, 1995-1998 Volkswagen Jetta, 1997-1997 Volkswagen EuroVan, 1999-1999 Volkswagen EuroVan, 1999-1999 Volkswagen Jetta, 2000-2000 Volkswagen EuroVan, 2000-2000 Volkswagen EuroVan
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Volkswagen Jetta
Item LocatedUnited States
Quantity1
Installation PositionUpper
item #10010APR
Note
from distributor to cylinder head
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Vaico V10-0418 Engine Coolant Thermostat Housing, Lower
VaicoPart # V10-0418
Vaico V10-0418 Engine Coolant Thermostat Housing, Lower
4.17 Reviews
$13.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1992-1992 Volkswagen Corrado, 1993-1993 Volkswagen Passat, 1993-1994 Volkswagen Corrado, 1994-1994 Volkswagen Jetta, 1994-1994 Volkswagen Passat, 1995-1997 Volkswagen Passat, 1995-1998 Volkswagen Golf, 1995-1998 Volkswagen Jetta, 1997-1997 Volkswagen EuroVan, 1999-1999 Volkswagen EuroVan, 1999-1999 Volkswagen Jetta, 2000-2000 Volkswagen EuroVan, 2000-2000 Volkswagen EuroVan
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Volkswagen Jetta
Item LocatedUnited States
Quantity1
Installation PositionLower
Part interchange
V10-0418, 18258, 021121133D, 21121133D, 902994, 1470000, 1001210021
item #100106AD
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Vaico 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: Volkswagen Jetta
Item LocatedUnited States
Quantity1
Part interchange
V10-0278, 23856, 52812, 06A121121C, 6A121121C, 6A121121F, 038121121D, 06A121121F, 
...View more
item #10010AAW
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Vaico V10-0285 Engine Coolant Thermostat Housing
VaicoPart # V10-0285
Vaico V10-0285 Engine Coolant Thermostat Housing
4.17 Reviews
$12.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1993-1993 Volkswagen Golf, 1993-1999 Volkswagen Jetta, 1994-1994 Volkswagen Golf, 1994-1994 Volkswagen Jetta, 1994-1999 Volkswagen Jetta, 1995-1995 Volkswagen Cabrio, 1995-1995 Volkswagen Golf, 1995-1995 Volkswagen Golf, 1995-1995 Volkswagen Golf, 1995-1995 Volkswagen Jetta, 1995-1995 Volkswagen Jetta, 1995-1996 Volkswagen Golf, 1995-1996 Volkswagen Passat, 1996-1996 Volkswagen Cabrio, 1996-1996 Volkswagen Golf, 1996-1996 Volkswagen Jetta, 1996-1996 Volkswagen Jetta, 1996-1997 Volkswagen Passat, 1997-1997 Volkswagen Jetta, 1997-1998 Volkswagen Cabrio
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Volkswagen Jetta
Item LocatedUnited States
Quantity1
Part interchange
V10-0285, 85073, 719043, 50048, 037121114, 37121114, 037121121A, 37121121A, 
...View more
item #100109NA
Note
with seal
Show less
Page 1 of 4

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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