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BMW 528i Thermostat

28 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 Housing Assembly for BMW F30 320i F10 528i E84 X1 X3Engine Coolant Thermostat Housing Assembly for BMW F30 320i F10 528i E84 X1 X3
A-Premium®Part # APTHA0063
Engine Coolant Thermostat Housing Assembly for BMW F30 320i F10 528i E84 X1 X3
4.685 Reviews
$54.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2014 - 2016 BMW 228i, 2015 - 2016 BMW 228i xDrive, 2012 - 2018 BMW 320i, 2013 - 2018 BMW 320i xDrive, 2012 - 2016 BMW 328i, 2014 - 2016 BMW 328i GT xDrive, 2013 - 2016 BMW 328i xDrive, 2014 - 2016 BMW 428i, 2015 - 2016 BMW 428i Gran Coupe, 2014 - 2016 BMW 428i xDrive, 2015 - 2016 BMW 428i xDrive Gran Coupe, 2012 - 2016 BMW 528i, 2012 - 2016 BMW 528i xDrive, 2012 - 2015 BMW X1, 2013 - 2017 BMW X3, 2015 - 2018 BMW X4, 2016 - 2018 BMW X5, 2012 - 2016 BMW Z4
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW 528i
Item LocatedUnited States
Quantity1
MaterialMetal
Part interchange
902-5135, 11538648791, 11538635689, 11538636595, 9025135
item #10052HA4
Show less
Engine Coolant Thermostat Housing Assembly for BMW F10 528i F01 740i 740Li 3.0L
A-Premium®Part # APTHA0064
Engine Coolant Thermostat Housing Assembly for BMW F10 528i F01 740i 740Li 3.0L
4.685 Reviews
$82.99
Low stock: Only 2 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2011 - 2011 BMW 528i, 2011 - 2012 BMW 740i, 2011 - 2012 BMW 740Li
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW 528i
Item LocatedUnited States
Quantity1
MaterialMetal
Part interchange
902-5172, 11538671517, 11537580627, 9025172
item #10052ER5
Show less
Thermostat Housing Assembly for BMW E90 323i 325i 328i 330i 335i 325xi 328xi 97℃
A-Premium®Part # APTHA0316
Thermostat Housing Assembly for BMW E90 323i 325i 328i 330i 335i 325xi 328xi 97℃
4.685 Reviews
$64.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2008 - 2008 BMW 323i, 2008 - 2008 BMW 528xi, 2006 - 2007 BMW 525xi, 2011 - 2013 BMW 335is, 2009 - 2010 BMW 335i xDrive, 2006 - 2007 BMW 530i, 2007 - 2010 BMW X3, 2008 - 2010 BMW 528i, 2009 - 2011 BMW 323i, 2006 - 2011 BMW Z4, 2007 - 2011 BMW X3, 2008 - 2010 BMW 535i, 2006 - 2007 BMW 525i, 2006 - 2007 BMW 530xi, 2006 - 2006 BMW 325i, 2006 - 2016 BMW Z4, 2006 - 2006 BMW 325i, 2007 - 2013 BMW 328i, 2011 - 2011 BMW 1 Series M, 2007 - 2008 BMW 328xi
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW 528i
Item LocatedUnited States
Quantity1
ConditionNew
item #1015HQCK
Note
【Note-1】 Start to Open Temperature: 97℃.
【Note-2】 This item comes with Sensor.
Show less
Automatic Transmission Oil Cooler Thermostat for BMW 525i 525xi 745i 750Li 645Ci
A-Premium®Part # APTHA0301
Automatic Transmission Oil Cooler Thermostat for BMW 525i 525xi 745i 750Li 645Ci
4.685 Reviews
$50.99
Low stock: Only 3 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2004 - 2007 BMW 525i, 2006 - 2007 BMW 525i, 2006 - 2007 BMW 525xi, 2008 - 2010 BMW 528i, 2008 - 2008 BMW 528xi, 2004 - 2007 BMW 530i, 2006 - 2007 BMW 530xi, 2004 - 2005 BMW 545i, 2006 - 2010 BMW 550i, 2004 - 2005 BMW 645Ci, 2006 - 2010 BMW 650i, 2002 - 2005 BMW 745i, 2002 - 2005 BMW 745Li, 2006 - 2008 BMW 750i, 2006 - 2008 BMW 750Li, 2004 - 2006 BMW 760i, 2003 - 2008 BMW 760Li
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW 528i
Item LocatedUnited States
ColorBlack
ConditionNew
item #10156EYA
Note
Automatic Transmission Oil Cooler Thermostat.
Show less
Thermostat Housing Assembly for BMW E39 528i 1997-1998 2.8L Aluminum
A-Premium®Part # APTHA0090
Thermostat Housing Assembly for BMW E39 528i 1997-1998 2.8L Aluminum
4.685 Reviews
$31.99
Low stock: Only 2 left
Edit ZIP code
2-year warranty
90 days free return
Fits 1997 - 1998 BMW 528i
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW 528i
Item LocatedUnited States
Quantity1
MaterialAluminum
Part interchange
902-5007, 85068, 11531740478
item #1005EYS6
Show less
Thermostat Housing Assembly for BMW E60 E82 E84 E90 128i 328i 335i 525i X3 Z4
A-Premium®Part # APTHA0027
Thermostat Housing Assembly for BMW E60 E82 E84 E90 128i 328i 335i 525i X3 Z4
4.685 Reviews
$54.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2011 - 2011 BMW 1 Series M, 2008 - 2013 BMW 128i, 2008 - 2010 BMW 135i, 2006 - 2011 BMW 323i, 2006 - 2006 BMW 325i, 2006 - 2006 BMW 325i, 2006 - 2006 BMW 325xi, 2007 - 2013 BMW 328i, 2012 - 2013 BMW 328i, 2009 - 2013 BMW 328i xDrive, 2007 - 2008 BMW 328xi, 2006 - 2006 BMW 330i, 2006 - 2006 BMW 330xi, 2007 - 2010 BMW 335i, 2009 - 2010 BMW 335i xDrive, 2011 - 2013 BMW 335is, 2007 - 2008 BMW 335xi, 2006 - 2007 BMW 525i, 2006 - 2007 BMW 525i, 2006 - 2007 BMW 525xi
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW 528i
Item LocatedUnited States
Quantity1
ColorBlack
item #10047V1Y
Note
This part comes with a cover and thermostat.
Show less
Thermostat Housing Assembly for BMW 320i E46 2001-2005 323is E46 Z3 Z4 525i X3
A-Premium®Part # APTHA0141
Thermostat Housing Assembly for BMW 320i E46 2001-2005 323is E46 Z3 Z4 525i X3
4.685 Reviews
$54.99
Low stock: Only 2 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2001 - 2005 BMW 320i, 2000 - 2000 BMW 323Ci, 2000 - 2000 BMW 323i, 1999 - 1999 BMW 323i, 1999 - 1999 BMW 323is, 2001 - 2006 BMW 325Ci, 2001 - 2005 BMW 325i, 2001 - 2005 BMW 325xi, 2000 - 2000 BMW 328Ci, 2000 - 2000 BMW 328i, 1999 - 1999 BMW 328i, 1999 - 1999 BMW 328is, 2006 - 2006 BMW 330Ci, 2001 - 2005 BMW 330Ci, 2001 - 2005 BMW 330i, 2001 - 2005 BMW 330xi, 2001 - 2005 BMW 525i, 1999 - 2000 BMW 528i, 2001 - 2005 BMW 530i, 2004 - 2006 BMW X3
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW 528i
Item LocatedUnited States
Quantity1
MaterialAluminum
item #1005EY1T
Note
This item comes with Thermostat and Sensor.
Show less
Thermostat Housing Assembly for BMW E46 323i 325i 328i 330i 525i 528i X3 X5 Z3
A-Premium®Part # APTHA0002
Thermostat Housing Assembly for BMW E46 323i 325i 328i 330i 525i 528i X3 X5 Z3
4.685 Reviews
$36.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2000 - 2000 BMW 323Ci, 1999 - 2000 BMW 323i, 2001 - 2006 BMW 325Ci, 2001 - 2005 BMW 325i, 2001 - 2005 BMW 325xi, 2000 - 2000 BMW 328Ci, 1999 - 2000 BMW 328i, 2001 - 2006 BMW 330Ci, 2001 - 2005 BMW 330i, 2001 - 2005 BMW 330xi, 2001 - 2005 BMW 525i, 1999 - 2000 BMW 528i, 2001 - 2005 BMW 530i, 2004 - 2005 BMW X3, 2004 - 2006 BMW X3, 2001 - 2006 BMW X5, 1999 - 2002 BMW Z3, 1999 - 2000 BMW Z3, 2001 - 2002 BMW Z3, 2003 - 2005 BMW Z4
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW 528i
Item LocatedUnited States
Quantity1
MaterialAluminum
ColorBlack
item #1003CXRU
Show less
Water Pump & Fan Clutch & Thermostat Assembly for BMW E36 E46 E39 E53 E83 E85
A-Premium®Part # FC001
Water Pump & Fan Clutch & Thermostat Assembly for BMW E36 E46 E39 E53 E83 E85
4.685 Reviews
$103.99
Low stock: Only 1 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2001 - 2005 BMW 320i, 2000 - 2000 BMW 323ci, 1999 - 2000 BMW 323i, 2001 - 2006 BMW 325Ci, 2001 - 2005 BMW 325i, 2001 - 2005 BMW 325xi, 2000 - 2000 BMW 328ci, 1999 - 2000 BMW 328i, 2001 - 2006 BMW 330ci, 2001 - 2005 BMW 330i, 2001 - 2005 BMW 330xi, 2001 - 2005 BMW 525i, 1999 - 2000 BMW 528i, 2001 - 2005 BMW 530i, 2004 - 2005 BMW X3, 2004 - 2006 BMW X3, 2001 - 2006 BMW X5, 1999 - 2002 BMW Z3, 1999 - 2000 BMW Z3, 2001 - 2002 BMW Z3
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW 528i
Item LocatedUnited States
Quantity3
Part interchange
1531437040, 11537509227, 111530139877, 1430825, TM1397, Z63001, 11517527799, 11517527910, 
...View more
item #1000V72Z
Show less
Thermostat for BMW 320i 323i 323is 325i 325is 328i 328is E36 525i 528i M3 Z3 89℃
A-Premium®Part # APTHE088
Thermostat for BMW 320i 323i 323is 325i 325is 328i 328is E36 525i 528i M3 Z3 89℃
4.685 Reviews
$23.99
Edit ZIP code
2-year warranty
90 days free return
Fits 1994 - 1995 BMW M3, 1992 - 1993 BMW 325is, 1991 - 1995 BMW 525i, 1996 - 1999 BMW 328is, 1995 - 1995 BMW 325i, 1994 - 1994 BMW 325i, 1996 - 1999 BMW M3, 1993 - 1993 BMW 325i, 1992 - 1992 BMW 325i, 1999 - 1999 BMW 328i, 1998 - 1999 BMW 323i, 1999 - 1999 BMW 528i, 1998 - 2000 BMW Z3, 1993 - 1995 BMW 320i, 1996 - 1998 BMW 328i, 1998 - 1999 BMW 323is, 1997 - 1999 BMW Z3
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW 528i
Item LocatedUnited States
Quantity1
ConditionNew
item #10177860
Note
【Note-1】 Start to Open Temperature: 89℃.
【Note-2】 For BMW 328i 1999, This item fits the model with Convertible, not Sedan.
【Note-3】 For BMW 325i 1992, This item fits the model with Engine Code M50.
【Note-4】 For BMW 325i 1993 & 1995, This item fits the model with Engine Code M50TU.
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Vemo V20-99-1294 Engine Coolant Thermostat Housing
VemoPart # V20-99-1294
Vemo V20-99-1294 Engine Coolant Thermostat Housing
57 Reviews
$124.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2012-2013 BMW 328i, 2012-2013 BMW 528i, 2012-2016 BMW 528i xDrive, 2012-2016 BMW Z4, 2013-2013 BMW 328i xDrive, 2013-2013 BMW X1, 2013-2013 BMW X3, 2013-2014 BMW 320i, 2013-2014 BMW 320i xDrive, 2013-2015 BMW X1, 2013-2015 BMW X1, 2014-2015 BMW 328i, 2014-2016 BMW 228i, 2014-2016 BMW 328i GT xDrive, 2014-2016 BMW 328i xDrive, 2014-2016 BMW 428i, 2014-2016 BMW 428i xDrive, 2014-2016 BMW 528i, 2014-2017 BMW X3, 2015-2016 BMW 228i xDrive
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW 528i
Item LocatedUnited States
Quantity1
Part interchange
V20-99-1294, TM25108, 9025135, 8620433108, 46404, 11537633476, 11538636595, 11537633477, 
...View more
item #1001QLKN
Note
Without gasket/seal
Show less
Vaico V20-7152 Engine Coolant Thermostat Housing
VaicoPart # V20-7152
Vaico V20-7152 Engine Coolant Thermostat Housing
4.17 Reviews
$27.99
Low stock: Only 2 left
Edit ZIP code
3-year warranty
90 days free return
Fits 1997-1998 BMW 528i
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW 528i
Item LocatedUnited States
Quantity1
MaterialPlastic
item #10010ALA
Note
with seal
Show less
Vemo V20-99-1271 Engine Coolant Thermostat
VemoPart # V20-99-1271
Vemo V20-99-1271 Engine Coolant Thermostat
57 Reviews
$42.99
Low stock: Only 3 left
Edit ZIP code
3-year warranty
90 days free return
Fits 1991-1995 BMW 525i, 1995-1995 BMW 320i, 1995-1995 BMW M3, 1996-1998 BMW 328i, 1996-1999 BMW 328is, 1997-1998 BMW 528i, 1997-1998 BMW Z3, 1998-1998 BMW 323i, 1998-1999 BMW 323is, 1999-1999 BMW 323i, 1999-1999 BMW 328i
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW 528i
Item LocatedUnited States
Quantity1
Part interchange
V20-99-1271, 78302S, 78302, TX2892D, 5302692, 27492, 38992, TX2888D, 
...View more
item #1001QRV9
Show less
ÜRO Parts 11537509227 Engine Coolant Thermostat Housing Assembly
ÜRO PartsPart # 11537509227
ÜRO Parts 11537509227 Engine Coolant Thermostat Housing Assembly
52 Reviews
$44.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1999-2000 BMW 323i, 1999-2000 BMW 328i, 1999-2000 BMW 528i, 2000-2000 BMW 323Ci, 2000-2000 BMW 328Ci, 2001-2002 BMW Z3, 2001-2004 BMW 320i, 2001-2005 BMW 325i, 2001-2005 BMW 325xi, 2001-2005 BMW 330i, 2001-2005 BMW 330xi, 2001-2005 BMW 525i, 2001-2005 BMW 530i, 2001-2006 BMW 325Ci, 2001-2006 BMW 330Ci, 2001-2006 BMW X5, 2003-2005 BMW Z4, 2004-2005 BMW X3, 2005-2005 BMW 320i, 2006-2006 BMW X3
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW 528i
Item LocatedUnited States
Quantity1
MaterialPPS
ColorBlack
item #1000ZRYX
Show less
ÜRO Parts 11538671517 Engine Coolant Thermostat / Water Inlet Assembly
ÜRO PartsPart # 11538671517
ÜRO Parts 11538671517 Engine Coolant Thermostat / Water Inlet Assembly
52 Reviews
$42.99
Low stock: Only 4 left
Edit ZIP code
3-year warranty
90 days free return
Fits 2011-2011 BMW 528i, 2011-2012 BMW 740Li, 2011-2012 BMW 740i
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW 528i
Item LocatedUnited States
Quantity1
ColorBlack
Part interchange
11538671517, 11538671517, 11537580627, 1430919, 902-5172, 34789, TM2197, 828-207, 
...View more
item #1000ZUA7
Show less
Vemo V20-99-1258-1 Engine Coolant Thermostat Kit
VemoPart # V20-99-1258-1
Vemo V20-99-1258-1 Engine Coolant Thermostat Kit
57 Reviews
$144.99
Low stock: Only 4 left
Edit ZIP code
3-year warranty
90 days free return
Fits 1999-1999 BMW 323i, 1999-1999 BMW 328i, 1999-2000 BMW 528i, 1999-2000 BMW Z3, 1999-2000 BMW Z3, 1999-2000 BMW Z3, 2000-2000 BMW 323Ci, 2000-2000 BMW 323i, 2000-2000 BMW 328Ci, 2000-2000 BMW 328i, 2001-2002 BMW Z3, 2001-2002 BMW Z3, 2001-2002 BMW Z3, 2001-2004 BMW 330Ci, 2001-2004 BMW 330i, 2001-2005 BMW 325i, 2001-2005 BMW 325xi, 2001-2005 BMW 330xi, 2001-2005 BMW 525i, 2001-2005 BMW 530i
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW 528i
Item LocatedUnited States
Quantity1
Part interchange
V20-99-1258-1, 254201, TM1397, 256101, 5351585, 5348601, 46797, 47197, 
...View more
item #1000X6WG
Note
With seal, With sensor
Show less
Beck/Arnley 143-0825 Engine Coolant Thermostat Housing Assembly
Beck/ArnleyPart # 143-0825
Beck/Arnley 143-0825 Engine Coolant Thermostat Housing Assembly
51 Reviews
$115.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1999-2000 BMW 323i, 1999-2000 BMW 328i, 1999-2000 BMW 528i, 1999-2000 BMW Z3, 1999-2002 BMW Z3, 2000-2000 BMW 323Ci, 2000-2000 BMW 328Ci, 2001-2002 BMW Z3, 2001-2005 BMW 320i, 2001-2005 BMW 325i, 2001-2005 BMW 325xi, 2001-2005 BMW 330i, 2001-2005 BMW 330xi, 2001-2005 BMW 525i, 2001-2005 BMW 530i, 2001-2006 BMW 325Ci, 2001-2006 BMW 330Ci, 2001-2006 BMW X5, 2003-2005 BMW Z4, 2004-2005 BMW X3
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW 528i
Item LocatedUnited States
Quantity1
Part interchange
143-0825
item #1000X7G0
Show less
ÜRO Parts 11537549476 Engine Coolant Thermostat / Water Inlet Assembly
ÜRO PartsPart # 11537549476
ÜRO Parts 11537549476 Engine Coolant Thermostat / Water Inlet Assembly
52 Reviews
$65.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2006-2006 BMW 325i, 2006-2006 BMW 325xi, 2006-2006 BMW 330i, 2006-2006 BMW 330xi, 2006-2007 BMW 525i, 2006-2007 BMW 525xi, 2006-2007 BMW 530i, 2006-2007 BMW 530xi, 2006-2008 BMW Z4, 2006-2008 BMW Z4, 2006-2008 BMW Z4, 2007-2008 BMW 328xi, 2007-2008 BMW 335xi, 2007-2010 BMW 335i, 2007-2010 BMW X3, 2007-2011 BMW 328i, 2008-2008 BMW 528xi, 2008-2008 BMW 535xi, 2008-2010 BMW 135i, 2008-2010 BMW 528i
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW 528i
Item LocatedUnited States
Quantity1
MaterialPlastic
ColorBlack
item #1000ZQ7H
Show less
ÜRO Parts 11537509227PRM Engine Coolant Thermostat / Water Inlet Assembly
ÜRO PartsPart # 11537509227PRM
ÜRO Parts 11537509227PRM Engine Coolant Thermostat / Water Inlet Assembly
52 Reviews
$58.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1998-1999 BMW 528i, 1999-1999 BMW 323i, 1999-1999 BMW 328i, 1999-1999 BMW Z3, 1999-1999 BMW Z3, 1999-2002 BMW Z3, 2000-2000 BMW 323Ci, 2000-2000 BMW 323i, 2000-2000 BMW 328Ci, 2000-2000 BMW 328i, 2000-2000 BMW 528i, 2000-2000 BMW Z3, 2000-2000 BMW Z3, 2001-2002 BMW Z3, 2001-2002 BMW Z3, 2001-2005 BMW 325i, 2001-2005 BMW 325xi, 2001-2005 BMW 330i, 2001-2005 BMW 330xi, 2001-2005 BMW 525i
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW 528i
Item LocatedUnited States
Quantity1
ColorSilver
Part interchange
11537509227PRM, 11531437040, 11537509227, 11530139877, 85955, Z63001, 11537509227PRM, URO-007365
item #1000ZSPC
Show less
Beck/Arnley 143-0731 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0731
Beck/Arnley 143-0731 Engine Coolant Thermostat
51 Reviews
$28.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1985-1985 BMW 325e, 1986-1987 BMW 325e, 1986-1987 BMW 325es, 1986-1988 BMW 325, 1986-1988 BMW 528e, 1986-1989 BMW 635CSi, 1986-1992 BMW 735i, 1986-1993 BMW 535i, 1987-1988 BMW M6, 1988-1988 BMW 535is, 1988-1988 BMW M5, 1988-1990 BMW 325is, 1988-1991 BMW 325iX, 1988-1992 BMW 735iL, 1988-1995 BMW 325i, 1989-1991 BMW 325i, 1989-1995 BMW 525i, 1991-1993 BMW M5, 1991-1995 BMW 318i, 1991-1995 BMW 318is
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW 528i
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0731
item #1000XDYW
Show less
Page 1 of 2

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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