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Thermostat

942 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 - Mahle TI 241 78Engine Coolant Thermostat - Mahle TI 241 78
SOLD OUT
MahlePart # TI 241 78
Engine Coolant Thermostat - Mahle TI 241 78
51 Reviews
$43.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2002-2006 Acura RSX, 2002-2006 Honda CR-V, 2002-2005 Honda Civic
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Item LocatedUnited States
Quantity1
Part interchange
TI 241 78, 33949, 14757, TI24178, 432-170, 19301-PNA-003
item #1000XSYQ
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Engine Coolant Thermostat - Mahle TX 167 82DSOLD OUT
MahlePart # TX 167 82D
Engine Coolant Thermostat - Mahle TX 167 82D
51 Reviews
$27.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 1996-2000 Toyota 4Runner, 1995-2004 Toyota Tacoma, 1995-2004 Toyota Tacoma, 1994-1998 Toyota T100, 1991-1997 Toyota Previa
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Item LocatedUnited States
Quantity1
Part interchange
TX 167 82D, 34008, 48418, TX16782D, 298-180, 90916-03120
item #1000XPG6
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Engine Coolant Thermostat - Mahle TX 186 82SOLD OUT
MahlePart # TX 186 82
Engine Coolant Thermostat - Mahle TX 186 82
51 Reviews
$21.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2004-2004 Kia Spectra, 2003-2003 Kia Spectra, 2002-2002 Kia Sportage, 2001-2005 Kia Rio, 2001-2001 Kia Sportage, 2000-2001 Kia Sephia
Check if this fits your vehicle
Item LocatedUnited States
Quantity1
Part interchange
TX 186 82, 33489S, 0K201-15-171A, 13868, TX18682, 240-192
item #1000XSLK
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Engine Coolant Thermostat - Mahle TI 250 78SOLD OUT
MahlePart # TI 250 78
Engine Coolant Thermostat - Mahle TI 250 78
51 Reviews
$49.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2012-2015 Honda Crosstour, 2010-2014 Acura TSX, 2009-2009 Acura TSX, 2008-2012 Honda Accord
Check if this fits your vehicle
Item LocatedUnited States
Quantity1
Part interchange
TI 250 78, 34703, 48767, TI25078, 729-172, 19301-R40-A01, 19301-R40-A02
item #1000XP4V
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Engine Coolant Thermostat - Mahle TI 249 82SOLD OUT
MahlePart # TI 249 82
Engine Coolant Thermostat - Mahle TI 249 82
51 Reviews
$41.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2012-2018 Toyota Prius C
Check if this fits your vehicle
Item LocatedUnited States
Quantity1
Part interchange
TI 249 82, 34832, 49708, TI24982, 752-180, 16031-21010, 16031-21010B
item #1000XSTE
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Engine Coolant Thermostat - Mahle TX 3 79DSOLD OUT
MahlePart # TX 3 79D
Engine Coolant Thermostat - Mahle TX 3 79D
51 Reviews
$26.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 1955-1963 Mercedes-Benz 190SL
Check if this fits your vehicle
Item LocatedUnited States
Quantity1
Part interchange
TX 3 79D, 3000.80, 33008, 121 200 03 15, 45358, TX379D, 200-180, 1.070.79.309
item #1000XNEY
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Engine Coolant Thermostat - Mahle TX 37 79SOLD OUT
MahlePart # TX 37 79
Engine Coolant Thermostat - Mahle TX 37 79
51 Reviews
$64.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2001-2003 BMW Z8, 2000-2003 BMW M5, 2000-2000 BMW Z8, 1991-1993 BMW M5
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Item LocatedUnited States
Quantity1
Part interchange
TX 37 79, 34791, TX3779, 11 53 1 315 063, 11 53 7 835 558, 11 53 1 407 772, 2.402.79
item #1000XP44
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Engine Coolant Thermostat - Mahle TX 26 71D1SOLD OUT
MahlePart # TX 26 71D1
Engine Coolant Thermostat - Mahle TX 26 71D1
51 Reviews
$32.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 1999-1999 Mercedes-Benz S500, 1994-1999 Mercedes-Benz S420, 1994-1998 Mercedes-Benz S500, 1994-1998 Mercedes-Benz SL500, 1994-1995 Mercedes-Benz E420, 1994-1994 Mercedes-Benz E500, 1993-1993 Mercedes-Benz 400SEL, 1993-1993 Mercedes-Benz 500SEC, 1992-1993 Mercedes-Benz 400E, 1992-1993 Mercedes-Benz 500E, 1992-1993 Mercedes-Benz 500SEL, 1992-1993 Mercedes-Benz 500SL, 1992-1992 Mercedes-Benz 400SE, 1990-1991 Mercedes-Benz 500SL, 1986-1991 Mercedes-Benz 420SEL, 1986-1991 Mercedes-Benz 560SEC, 1986-1991 Mercedes-Benz 560SEL, 1986-1989 Mercedes-Benz 560SL
Check if this fits your vehicle
Item LocatedUnited States
Quantity1
Part interchange
TX 26 71D1, 4137.71D, 14578, TX2671D1, 2.118.71.316
item #1000XT23
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Engine Coolant Thermostat - Mahle TX 348 82DSOLD OUT
MahlePart # TX 348 82D
Engine Coolant Thermostat - Mahle TX 348 82D
51 Reviews
$25.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2017-2017 Hyundai Elantra, 2017-2017 Kia Rio, 2016-2017 Hyundai Tucson, 2016-2017 Kia Optima, 2016-2016 Kia Rio, 2016-2016 Kia Rio, 2016-2016 Kia Rio, 2016-2016 Kia Rio, 2016-2016 Kia Rio, 2015-2017 Hyundai Sonata, 2014-2017 Kia Forte Koup, 2014-2017 Kia Forte5, 2012-2017 Hyundai Accent, 2012-2017 Hyundai Veloster, 2012-2015 Kia Rio, 2010-2017 Kia Soul
Check if this fits your vehicle
Item LocatedUnited States
Quantity1
Part interchange
TX 348 82D, 34802, 25500-2B000, 143-0900, 15138, TX34882D, 726-180
item #1000XLZT
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Engine Coolant Thermostat - Mahle TI 235 95SOLD OUT
MahlePart # TI 235 95
Engine Coolant Thermostat - Mahle TI 235 95
51 Reviews
$37.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2011-2018 Chrysler 300, 2011-2018 Dodge Challenger, 2011-2018 Dodge Charger
Check if this fits your vehicle
Item LocatedUnited States
Quantity1
Part interchange
TI 235 95, 34776, 49549, TI23595, 824-203, 5184 977AD, 5184 977AH, 5184 977AE
item #1000XRXA
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Engine Coolant Thermostat - Upper - Mahle TX 258 55SOLD OUT
MahlePart # TX 258 55
Engine Coolant Thermostat - Upper - Mahle TX 258 55
51 Reviews
$30.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2015-2015 Subaru Legacy, 2015-2015 Subaru Outback, 2015-2015 Subaru Outback, 2015-2015 Subaru Outback, 2015-2015 Subaru Outback, 2015-2015 Subaru Outback, 2015-2015 Subaru Outback, 2014-2016 Subaru Forester, 2013-2015 Subaru BRZ, 2013-2015 Subaru XV Crosstrek, 2012-2016 Subaru Impreza, 2012-2016 Subaru Impreza, 2012-2016 Subaru Impreza, 2012-2016 Subaru Impreza, 2012-2016 Subaru Impreza, 2012-2016 Subaru Impreza, 2012-2015 Subaru Impreza
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Item LocatedUnited States
Quantity1
Installation PositionUpper
Part interchange
TX 258 55, TX 258 55, 21210 AA190
item #1000XQTQ
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Engine Coolant Thermostat - Mahle TX 34 82DSOLD OUT
MahlePart # TX 34 82D
Engine Coolant Thermostat - Mahle TX 34 82D
51 Reviews
$29.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2005-2006 Audi A8 Quattro, 2004-2007 Volkswagen Touareg, 2004-2006 Volkswagen Phaeton, 2003-2004 Audi RS6, 2002-2003 Audi S6, 2001-2004 Audi A6 Quattro, 2001-2003 Audi S8, 2000-2004 Audi A8 Quattro, 2000-2000 Audi A6 Quattro, 1997-1999 Audi A8, 1997-1999 Audi A8 Quattro, 1995-1995 Audi 90, 1995-1995 Audi 90 Quattro
Check if this fits your vehicle
Item LocatedUnited States
Quantity1
Part interchange
TX 34 82D, 33069, 48049, 304-192, TX3482D, 077 121 113 C, 077 121 113 D, 2.161.82.312
item #1000XRCK
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Engine Coolant Thermostat - Mahle TX 34 87DSOLD OUT
MahlePart # TX 34 87D
Engine Coolant Thermostat - Mahle TX 34 87D
51 Reviews
$31.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2005-2006 Audi A8 Quattro, 2004-2007 Volkswagen Touareg, 2004-2006 Volkswagen Phaeton, 2003-2004 Audi RS6, 2002-2003 Audi S6, 2001-2004 Audi A6 Quattro, 2001-2003 Audi S8, 2000-2004 Audi A8 Quattro, 2000-2000 Audi A6 Quattro
Check if this fits your vehicle
Item LocatedUnited States
Quantity1
Part interchange
TX 34 87D, 33069, TX3487D, 304-192, 077 121 113 D, 077 121 113 C, 077 121 113 B, 2.161.87.312
item #1000XRH3
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Engine Coolant Thermostat - Mahle TX 202 90DSOLD OUT
MahlePart # TX 202 90D
Engine Coolant Thermostat - Mahle TX 202 90D
51 Reviews
$31.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2011-2011 Volvo C30, 2011-2011 Volvo C30, 2010-2011 Volvo C30, 2010-2011 Volvo C30, 2010-2011 Volvo C70, 2010-2011 Volvo S40, 2008-2009 Volvo C30, 2008-2009 Volvo C30, 2007-2011 Volvo S40, 2007-2011 Volvo V50, 2007-2010 Volvo S40, 2006-2009 Volvo C70, 2005-2006 Volvo S40, 2005-2006 Volvo V50, 2005-2006 Volvo V50, 2004-2004 Volvo S40, 2004-2004 Volvo S40
Check if this fits your vehicle
Item LocatedUnited States
Quantity1
Part interchange
TX 202 90D, TX20290D
item #1000XQ7W
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Engine Coolant Thermostat - Mahle TX 24 87DSOLD OUT
MahlePart # TX 24 87D
Engine Coolant Thermostat - Mahle TX 24 87D
51 Reviews
$31.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 1985-1991 Volkswagen Vanagon, 1985-1985 Volkswagen Transporter, 1983-1984 Volkswagen Vanagon
Check if this fits your vehicle
Item LocatedUnited States
Quantity1
Part interchange
TX 24 87D, 33079, 13649, TX2487D, 273-192, 025 121 113 F
item #1000XPE2
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Engine Coolant Thermostat - Mahle TX 161 82DSOLD OUT
MahlePart # TX 161 82D
Engine Coolant Thermostat - Mahle TX 161 82D
51 Reviews
$27.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2016-2018 Honda HR-V, 2013-2015 Acura ILX, 2006-2015 Honda Civic, 2003-2005 Honda Civic
Check if this fits your vehicle
Item LocatedUnited States
Quantity1
Part interchange
TX 161 82D, 33568, 13878, TX16182D, 242-192, 19301-PWA-305, 19301-PZA-305, 19301-RNA-315
item #1000XRZU
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Engine Coolant Thermostat - Mahle TM 21 97SOLD OUT
MahlePart # TM 21 97
Engine Coolant Thermostat - Mahle TM 21 97
51 Reviews
$99.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2011-2012 BMW 740i, 2011-2012 BMW 740Li, 2011-2011 BMW 528i
Check if this fits your vehicle
Item LocatedUnited States
Quantity1
Part interchange
TM 21 97, 34789, 49622, TM2197, 828-207, 11 53 7 580 627
item #1000XQDZ
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Engine Coolant Thermostat - Mahle TM 17 98SOLD OUT
MahlePart # TM 17 98
Engine Coolant Thermostat - Mahle TM 17 98
51 Reviews
$106.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2009-2011 Ford Focus, 2007-2011 Ford Focus, 2007-2011 Ford Focus, 2007-2011 Ford Focus, 2005-2006 Ford Focus, 2005-2006 Ford Focus, 2005-2006 Ford Focus, 2005-2006 Ford Focus, 2001-2003 Ford Ranger
Check if this fits your vehicle
Item LocatedUnited States
Quantity1
Part interchange
TM 17 98, RT1157, 34042, 48672, 604-208, TM1798, 1S7Z-8575-AG
item #1000XR1W
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Engine Coolant Thermostat - Mahle TM 45 100DSOLD OUT
MahlePart # TM 45 100D
Engine Coolant Thermostat - Mahle TM 45 100D
51 Reviews
$99.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2012-2012 Mercedes-Benz C300, 2011-2011 Mercedes-Benz E350, 2010-2013 Mercedes-Benz S400, 2010-2012 Mercedes-Benz GLK350, 2010-2011 Mercedes-Benz C300, 2010-2011 Mercedes-Benz C300, 2010-2011 Mercedes-Benz C300, 2010-2011 Mercedes-Benz C300, 2010-2011 Mercedes-Benz C300, 2010-2011 Mercedes-Benz ML350, 2010-2011 Mercedes-Benz ML450, 2010-2011 Mercedes-Benz R350, 2010-2010 Mercedes-Benz C300, 2009-2011 Mercedes-Benz SLK300, 2008-2009 Mercedes-Benz C300, 2006-2011 Mercedes-Benz C350, 2006-2011 Mercedes-Benz SLK350, 2006-2010 Mercedes-Benz E350, 2006-2009 Mercedes-Benz CLK350, 2006-2009 Mercedes-Benz ML350
Check if this fits your vehicle
Item LocatedUnited States
Quantity1
Part interchange
TM 45 100D, 34704, 272 200 04 15, 272 200 01 15, 272 200 00 15, 49382, 668-212, TM45100D
item #1000XT39
Show less
Engine Coolant Thermostat - Mahle TI 256 77DSOLD OUT
MahlePart # TI 256 77D
Engine Coolant Thermostat - Mahle TI 256 77D
51 Reviews
$40.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2008-2008 INFINITI G37, 2007-2007 INFINITI G35, 2003-2008 INFINITI FX35, 2003-2006 INFINITI G35, 2003-2006 Nissan 350Z, 2001-2004 Nissan Pathfinder, 2001-2003 INFINITI QX4
Check if this fits your vehicle
Item LocatedUnited States
Quantity1
Part interchange
TI 256 77D, 21200-4W000, 21200-4W010, 21200-4W01B, 33940, 14668, TI25677D, 391-170
item #1000XQZN
Show less
Page 35 of 48

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