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Audi A4 Thermostat

47 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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ÜRO Parts 078121121J Engine Coolant Thermostat HousingÜRO Parts 078121121J Engine Coolant Thermostat Housing
ÜRO PartsPart # 078121121J
ÜRO Parts 078121121J Engine Coolant Thermostat Housing
52 Reviews
$142.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1995-1995 Audi 90, 1995-1995 Audi 90 Quattro, 1995-1995 Audi Cabriolet, 1995-1999 Audi A6 Quattro, 1995-2000 Audi A6, 1996-1996 Audi A4, 1996-1996 Audi A4 Quattro, 1996-1998 Audi Cabriolet, 1997-2001 Audi A4, 1997-2001 Audi A4 Quattro, 2000-2000 Audi A6 Quattro, 2000-2000 Audi A6 Quattro, 2000-2002 Audi S4, 2001-2001 Audi A6, 2001-2001 Audi A6 Quattro, 2001-2001 Audi A6 Quattro, 1998-2000 Volkswagen Passat, 2001-2001 Volkswagen Passat
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A4
Item LocatedUnited States
Quantity1
ColorSilver
Part interchange
078121121J, 078121121J, 078121121H, 078121121F, 078121121D, 143-0709, URO-009859
item #1000ZT5K
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ÜRO Parts 030121121B Engine Coolant Thermostat Housing
ÜRO PartsPart # 030121121B
ÜRO Parts 030121121B Engine Coolant Thermostat Housing
52 Reviews
$11.99
Low stock: Only 4 left
Edit ZIP code
3-year warranty
90 days free return
Fits 1997-1997 Audi A4, 1997-1997 Audi A4 Quattro, 1998-1998 Audi A4 Quattro, 1998-2001 Audi A4, 1999-2001 Audi A4 Quattro, 2002-2002 Audi A4, 2002-2002 Audi A4 Quattro, 1998-2000 Volkswagen Passat
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A4
Item LocatedUnited States
Quantity1
Part interchange
030121121B, 030121121B, 147-0029, 902-995, CH-9995, V10-0283, URO-000122
item #1000ZTHZ
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ÜRO Parts 06B121121 Engine Coolant Thermostat Housing
ÜRO PartsPart # 06B121121
ÜRO Parts 06B121121 Engine Coolant Thermostat Housing
52 Reviews
$12.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2001-2001 Audi A4, 2001-2001 Audi A4 Quattro, 2000-2000 Volkswagen Passat, 2001-2005 Volkswagen Passat
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A4
Item LocatedUnited States
Quantity1
Part interchange
06B121121, 06B121121L, 06B121121, 147-0043, CH-9991, V10-8198, URO-008057
item #1000ZTUU
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ÜRO Parts 06E121111M Engine Coolant Thermostat / Water Inlet Assembly
ÜRO PartsPart # 06E121111M
ÜRO Parts 06E121111M Engine Coolant Thermostat / Water Inlet Assembly
52 Reviews
$55.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2005-2005 Audi A6 Quattro, 2005-2007 Audi A4, 2005-2008 Audi A4 Quattro, 2006-2007 Audi A6 Quattro, 2006-2011 Audi A6, 2008-2008 Audi A4, 2008-2008 Audi A6 Quattro, 2008-2010 Audi A5 Quattro, 2009-2009 Audi A4 Quattro, 2009-2010 Audi Q5, 2011-2012 Audi Q5
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A4
Item LocatedUnited States
Quantity1
MaterialPA66/GF30
ColorBlack
item #1000ZQYV
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Vemo V15-99-2053 Engine Coolant Thermostat Housing
VemoPart # V15-99-2053
Vemo V15-99-2053 Engine Coolant Thermostat Housing
57 Reviews
$43.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2009-2009 Audi TT, 2009-2009 Audi TT Quattro, 2010-2013 Audi TT Quattro, 2014-2014 Audi TT Quattro, 2017-2018 Audi A4 Quattro, 2017-2018 Audi A4 allroad, 2018-2018 Audi A5 Quattro, 2018-2018 Audi A5 Quattro, 2018-2018 Audi A5 Quattro, 2018-2018 Audi A5 Quattro, 2018-2018 Audi A5 Quattro, 2018-2018 Audi A5 Quattro, 2018-2018 Audi A5 Quattro, 2018-2018 Audi A5 Quattro, 2018-2018 Audi A5 Sportback, 2005-2005 Volkswagen Jetta, 2006-2006 Volkswagen Jetta, 2006-2010 Volkswagen Beetle, 2007-2007 Volkswagen Jetta, 2007-2009 Volkswagen Rabbit
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A4
Item LocatedUnited States
Quantity1
Part interchange
V15-99-2053, 1K0121113A
item #1001QQWK
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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 A4
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0149
item #1000XG3Z
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ÜRO Parts 06B121111K Engine Coolant Thermostat / Water Inlet Assembly
ÜRO PartsPart # 06B121111K
ÜRO Parts 06B121111K Engine Coolant Thermostat / Water Inlet Assembly
52 Reviews
$81.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2002-2002 Audi A4, 2002-2002 Audi A4 Quattro, 2003-2005 Audi A4 Quattro, 2003-2006 Audi A4
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A4
Item LocatedUnited States
Quantity1
MaterialPA66
ColorBlack
item #1000ZQE6
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Beck/Arnley 143-0881 Engine Coolant Thermostat Housing Assembly
Beck/ArnleyPart # 143-0881
Beck/Arnley 143-0881 Engine Coolant Thermostat Housing Assembly
51 Reviews
$60.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2005-2008 Audi A4 Quattro, 2005-2008 Audi A4 Quattro, 2005-2008 Audi A6 Quattro, 2006-2006 Audi A6, 2007-2007 Audi A6, 2007-2009 Audi A4 Quattro, 2008-2008 Audi A6, 2008-2009 Audi A5 Quattro, 2009-2009 Audi Q5, 2009-2010 Audi A6, 2010-2010 Audi A5 Quattro, 2010-2012 Audi Q5, 2011-2011 Audi A6
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A4
Item LocatedUnited States
Quantity1
Part interchange
143-0881
item #1000XAVV
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Vemo V15-99-2003 Engine Coolant Thermostat
VemoPart # V15-99-2003
Vemo V15-99-2003 Engine Coolant Thermostat
57 Reviews
$19.99
Low stock: Only 5 left
Edit ZIP code
3-year warranty
90 days free return
Fits 1999-1999 Audi A4, 1999-1999 Audi A4 Quattro, 1999-1999 Audi A6, 1999-1999 Audi A6 Quattro, 2000-2000 Audi A6, 2000-2000 Audi A6 Quattro, 2000-2001 Audi A4, 2000-2001 Audi A4 Quattro, 2001-2001 Audi A6, 2001-2001 Audi A6 Quattro, 2001-2001 Audi A6 Quattro, 1999-1999 Volkswagen Passat, 1999-1999 Volkswagen Passat, 2000-2000 Volkswagen Passat, 2000-2000 Volkswagen Passat, 2000-2000 Volkswagen Passat, 2001-2001 Volkswagen Passat, 2001-2001 Volkswagen Passat, 2001-2001 Volkswagen Passat, 2001-2001 Volkswagen Passat
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A4
Item LocatedUnited States
Quantity1
Part interchange
V15-99-2003, TX3092D, 214592312, 214592, 65497T, 78401S, 78401, 30492, 
...View more
item #1001QQRL
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Beck/Arnley 143-0849 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0849
Beck/Arnley 143-0849 Engine Coolant Thermostat
51 Reviews
$29.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1997-2001 Audi A4 Quattro, 1997-2002 Audi A4, 2000-2002 Audi TT Quattro, 2000-2006 Audi TT, 1998-2005 Volkswagen Beetle, 1998-2005 Volkswagen Passat, 1999-2005 Volkswagen Beetle, 1999-2005 Volkswagen Jetta, 1999-2006 Volkswagen Golf, 2000-2005 Volkswagen Jetta, 2000-2006 Volkswagen Golf, 2011-2011 Volkswagen Jetta, 2011-2011 Volkswagen Jetta, 2011-2011 Volkswagen Jetta, 2011-2013 Volkswagen Jetta, 2011-2014 Volkswagen Jetta, 2011-2014 Volkswagen Jetta, 2012-2014 Volkswagen Jetta, 2013-2014 Volkswagen Jetta
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A4
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0849
item #1000XD9D
Show less
Beck/Arnley 143-0816 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0816
Beck/Arnley 143-0816 Engine Coolant Thermostat
51 Reviews
$30.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1995-1999 Audi A6 Quattro, 1995-2001 Audi A6, 1997-2001 Audi A4 Quattro, 2000-2001 Audi A4, 2000-2001 Audi A6 Quattro, 2000-2000 Volkswagen Passat, 2000-2005 Volkswagen Passat, 2000-2005 Volkswagen Passat, 2001-2002 Volkswagen Passat, 2001-2005 Volkswagen Passat, 2003-2004 Volkswagen Passat, 2005-2005 Volkswagen Passat
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A4
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0816
item #1000XGWA
Show less
Beck/Arnley 143-0867 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0867
Beck/Arnley 143-0867 Engine Coolant Thermostat
51 Reviews
$48.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2008-2008 Audi A3, 2009-2009 Audi A3, 2009-2009 Audi A3 Quattro, 2009-2009 Audi TT, 2009-2009 Audi TT Quattro, 2009-2014 Audi A4 Quattro, 2009-2016 Audi A4, 2010-2010 Audi A3, 2010-2010 Audi A5, 2010-2011 Audi A3, 2010-2011 Audi A3, 2010-2013 Audi A3, 2010-2013 Audi A3, 2010-2013 Audi A3 Quattro, 2010-2013 Audi TT Quattro, 2010-2016 Audi A5 Quattro, 2011-2011 Audi A5, 2011-2012 Audi Q5, 2012-2013 Audi A3, 2012-2013 Audi A6
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A4
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0867
item #1000XHVX
Show less
Vemo V15-99-1990 Engine Coolant Thermostat
VemoPart # V15-99-1990
Vemo V15-99-1990 Engine Coolant Thermostat
57 Reviews
$32.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1990-1994 Audi V8 Quattro, 1992-1994 Audi 100, 1992-1994 Audi 100 Quattro, 1993-1995 Audi 90, 1993-1995 Audi 90 Quattro, 1994-1998 Audi Cabriolet, 1995-1998 Audi A6, 1995-1998 Audi A6 Quattro, 1996-1996 Audi A4, 1996-1996 Audi A4 Quattro, 1997-1998 Audi A4, 1997-1998 Audi A4 Quattro, 1997-1999 Audi A8, 1997-1999 Audi A8 Quattro, 1999-1999 Audi A4, 1999-1999 Audi A4 Quattro, 1999-1999 Audi A6, 1999-1999 Audi A6 Quattro, 2000-2002 Audi S4, 2000-2004 Audi A6 Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A4
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
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 A4
Item LocatedUnited States
Quantity1
Part interchange
143-0709
item #1000XG5E
Show less
Beck/Arnley 143-0913 Engine Coolant Thermostat Housing Assembly
Beck/ArnleyPart # 143-0913
Beck/Arnley 143-0913 Engine Coolant Thermostat Housing Assembly
51 Reviews
$263.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2015-2016 Audi A3, 2015-2020 Audi A3 Quattro, 2015-2020 Audi S3, 2016-2018 Audi A6, 2016-2023 Audi A6 Quattro, 2016-2023 Audi TT Quattro, 2016-2023 Audi TTS Quattro, 2017-2020 Audi A3, 2017-2020 Audi A4, 2017-2023 Audi A4 Quattro, 2017-2023 Audi A4 allroad, 2017-2023 Audi Q7, 2018-2023 Audi A5 Quattro, 2018-2023 Audi A5 Sportback, 2018-2023 Audi Q5, 2019-2023 Audi Q3, 2020-2023 Audi Q5 PHEV, 2021-2022 Audi A7 Sportback, 2021-2023 Audi Q5 Sportback, 2022-2023 Audi A3
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A4
Item LocatedUnited States
Quantity1
Part interchange
143-0913
item #1000X8PQ
Show less
Beck/Arnley 143-0860 Engine Coolant Thermostat Housing Assembly
Beck/ArnleyPart # 143-0860
Beck/Arnley 143-0860 Engine Coolant Thermostat Housing Assembly
51 Reviews
$71.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2005-2009 Audi A4, 2005-2009 Audi A4 Quattro, 2006-2007 Audi A4
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A4
Item LocatedUnited States
Quantity1
Part interchange
143-0860
item #1000X96W
Show less
Beck/Arnley 143-0873 Engine Coolant Thermostat Housing Assembly
Beck/ArnleyPart # 143-0873
Beck/Arnley 143-0873 Engine Coolant Thermostat Housing Assembly
51 Reviews
$104.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2002-2005 Audi A4 Quattro, 2002-2006 Audi A4
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A4
Item LocatedUnited States
Quantity1
Part interchange
143-0873
item #1000X7K0
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Engine Coolant Thermostat - Mahle TX 30 92D
MahlePart # TX 30 92D
Engine Coolant Thermostat - Mahle TX 30 92D
51 Reviews
$27.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2000-2001 Audi A4, 2000-2001 Audi A4 Quattro, 2000-2001 Audi A6, 2000-2001 Audi A6 Quattro, 2000-2005 Volkswagen Passat
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A4
Item LocatedUnited States
Quantity1
Part interchange
TX 30 92D, TH6533.92J, 4274.92D, 34779, 13649, 304-198, TX3092D, 078 121 113 G, 
...View more
item #1000XRN3
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Engine Coolant Thermostat - Mahle TI 7 87
MahlePart # TI 7 87
Engine Coolant Thermostat - Mahle TI 7 87
51 Reviews
$46.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2005-2005 Audi A4, 2005-2005 Audi A4, 2005-2005 Audi A4 Quattro, 2005-2005 Audi A4 Quattro, 2006-2007 Audi A4, 2006-2009 Audi A4, 2006-2009 Audi A4 Quattro, 2008-2008 Audi A4
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A4
Item LocatedUnited States
Quantity1
Part interchange
TI 7 87, 34069, 49099, 576-189, 06D 121 111 G, TI787, 1.329.87
item #1000XRCU
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Engine Coolant Thermostat - Mahle TI 205 92D
MahlePart # TI 205 92D
Engine Coolant Thermostat - Mahle TI 205 92D
51 Reviews
$54.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2002-2004 Audi A6, 2002-2004 Audi A6 Quattro, 2002-2004 Audi A6 Quattro, 2002-2005 Audi A4, 2002-2006 Audi A4 Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A4
Item LocatedUnited States
Quantity1
Part interchange
TI 205 92D, 4814.92D, 15288, TI20592D, 914-198, 06C 121 111 E
item #1000XNG4
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Page 2 of 3

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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