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Thermostat

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Engine Coolant Thermostat Housing Assy for BMW 540i 740i 1997 1998 740iL 105℃Engine Coolant Thermostat Housing Assy for BMW 540i 740i 1997 1998 740iL 105℃
A-Premium®Part # APTHA0337
Engine Coolant Thermostat Housing Assy for BMW 540i 740i 1997 1998 740iL 105℃
4.651 Reviews
$45.99
Quantity Less than 2
Edit ZIP code
2-year warranty
90 days free return
Fits 1997 - 1998 BMW 540i, 1997 - 1998 BMW 740i, 1996 - 1998 BMW 740iL
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW
Item LocatedUnited States
Quantity1
MaterialMetal/Rubber
Part interchange
11531437526, 34727, 470221, 902818, 902-818
ConditionNew
item #1016V9AX
Note
【Note-1】 Start to Open Temperature: 105℃.
【Note-2】 This item includes Thermostat.
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Vemo V20-99-1303 Engine Coolant Thermostat Kit
VemoPart # V20-99-1303
Vemo V20-99-1303 Engine Coolant Thermostat Kit
53 Reviews
$193.99
Quantity Less than 3
Edit ZIP code
3-year warranty
90 days free return
Fits 2012-2013 BMW 335i, 2013-2013 BMW 335i xDrive, 2013-2014 BMW ActiveHybrid 3, 2014-2015 BMW 335i, 2014-2015 BMW 335i xDrive, 2014-2015 BMW M235i, 2014-2016 BMW 335i GT xDrive, 2014-2016 BMW 435i, 2014-2016 BMW 435i xDrive, 2014-2017 BMW X5, 2014-2017 BMW X5, 2015-2015 BMW ActiveHybrid 3, 2015-2016 BMW 435i Gran Coupe, 2015-2016 BMW 435i xDrive Gran Coupe, 2015-2016 BMW M235i xDrive, 2015-2017 BMW X6, 2015-2017 BMW X6, 2016-2016 BMW M2, 2016-2016 BMW M235i, 2017-2017 BMW M2
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Vehicle: BMW
Item LocatedUnited States
Quantity1
Part interchange
V20-99-1303, 11537598865, 11532394968, 2394968, 7598865
item #1000X88G
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Vemo V20-99-1258-1 Engine Coolant Thermostat Kit
VemoPart # V20-99-1258-1
Vemo V20-99-1258-1 Engine Coolant Thermostat Kit
53 Reviews
$144.99
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, 2001-2006 BMW 325Ci, 2001-2006 BMW X5, 2003-2005 BMW Z4, 2004-2005 BMW X3, 2005-2005 BMW 330Ci, 2005-2005 BMW 330i, 2006-2006 BMW 330Ci, 2006-2006 BMW X3
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW
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
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Vemo V20-99-1268 Engine Coolant Thermostat Kit
VemoPart # V20-99-1268
Vemo V20-99-1268 Engine Coolant Thermostat Kit
53 Reviews
$148.99
Only 1 item left in stock
Edit ZIP code
3-year warranty
90 days free return
Fits 1999-2001 BMW 740i, 1999-2001 BMW 740iL, 1999-2003 BMW 540i, 2000-2000 BMW X5, 2001-2001 BMW X5, 2002-2003 BMW X5, 2002-2003 BMW X5, 2003-2003 BMW Z8, 2003-2004 Land Rover Range Rover, 2005-2005 Land Rover Range Rover
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Vehicle: BMW
Item LocatedUnited States
Quantity1
Part interchange
V20-99-1268, 254701, TM12105, 468105, 1601324695, 33935, TH32205G1, 902819, 
...View more
item #1000X9CP
Note
With seal
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ÜRO Parts 11537598865 Engine Coolant Thermostat / Water Inlet Assembly
ÜRO PartsPart # 11537598865
ÜRO Parts 11537598865 Engine Coolant Thermostat / Water Inlet Assembly
51 Reviews
$77.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2012-2013 BMW 335i, 2012-2013 BMW 335i, 2012-2013 BMW 335i, 2012-2013 BMW 335i, 2012-2013 BMW 335i, 2013-2013 BMW 335i xDrive, 2013-2015 BMW ActiveHybrid 3, 2014-2015 BMW 335i, 2014-2015 BMW 335i xDrive, 2014-2016 BMW 335i GT xDrive, 2014-2016 BMW 435i, 2014-2016 BMW 435i xDrive, 2014-2016 BMW M235i, 2014-2018 BMW X5, 2014-2018 BMW X5, 2015-2016 BMW 435i Gran Coupe, 2015-2016 BMW 435i xDrive Gran Coupe, 2015-2016 BMW M235i xDrive, 2015-2017 BMW X6, 2015-2017 BMW X6, 2016-2018 BMW M2, 2018-2018 BMW X6, 2019-2019 BMW X6, 2019-2019 BMW X6
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW
Item LocatedUnited States
Quantity1
ColorBlack
Part interchange
11537598865, 11532394968, 11537598865, 1430940, 902-5825, 937-217, 49822, URO-015700
item #1000ZQXZ
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ÜRO Parts 11531743017 Engine Coolant Thermostat / Water Inlet Assembly
ÜRO PartsPart # 11531743017
ÜRO Parts 11531743017 Engine Coolant Thermostat / Water Inlet Assembly
51 Reviews
$36.99
Quantity Less than 3
Edit ZIP code
3-year warranty
90 days free return
Fits 1996-1996 BMW Z3, 1996-1997 BMW 318is, 1996-1998 BMW 318i, 1996-1999 BMW 318ti, 1997-1997 BMW Z3, 1998-1998 BMW Z3
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW
Item LocatedUnited States
Quantity1
ColorBlack
Part interchange
11531743017, 11531743017, 11531432884, 1430840, TI2495, 902-5118, 85962, 33937, 
...View more
item #1000ZSP2
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ÜRO Parts 11531436386 Engine Coolant Thermostat / Water Inlet Assembly
ÜRO PartsPart # 11531436386
ÜRO Parts 11531436386 Engine Coolant Thermostat / Water Inlet Assembly
51 Reviews
$55.99
Quantity Less than 5
Edit ZIP code
3-year warranty
90 days free return
Fits 1998-1998 BMW 540i, 1999-1999 BMW 540i, 1999-1999 BMW 740i, 1999-1999 BMW 740iL, 2000-2000 BMW X5, 2000-2001 BMW 740i, 2000-2001 BMW 740iL, 2000-2003 BMW 540i, 2001-2001 BMW X5, 2002-2003 BMW X5, 2002-2003 BMW X5, 2003-2003 BMW Z8, 2003-2005 Land Rover Range Rover
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW
Item LocatedUnited States
Quantity1
ColorSilver
Part interchange
11531436386, 11531436386, PEL000060, 1430841, 902-819, 33935, TM12105, CTA0034, 
...View more
item #1000ZPUL
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ÜRO Parts 11538671516 Engine Coolant Thermostat / Water Inlet Assembly
ÜRO PartsPart # 11538671516
ÜRO Parts 11538671516 Engine Coolant Thermostat / Water Inlet Assembly
51 Reviews
$64.99
Quantity Less than 2
Edit ZIP code
3-year warranty
90 days free return
Fits 2010-2017 BMW 535i GT, 2011-2016 BMW 535i, 2011-2016 BMW 535i xDrive, 2011-2017 BMW 535i GT xDrive, 2012-2016 BMW ActiveHybrid 5, 2013-2015 BMW 740i, 2014-2015 BMW 640i xDrive, 2014-2015 BMW 640i xDrive Gran Coupe
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW
Item LocatedUnited States
Quantity1
ColorBlack
Part interchange
11538671516, 11538671516, 11537601159, 902-5173, 34781, TM21103, 828-217, 49602, 
...View more
item #1000ZRPZ
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ÜRO Parts 11531437526 Engine Coolant Thermostat / Water Inlet Assembly
ÜRO PartsPart # 11531437526
ÜRO Parts 11531437526 Engine Coolant Thermostat / Water Inlet Assembly
51 Reviews
$55.99
Only 1 item left in stock
Edit ZIP code
3-year warranty
90 days free return
Fits 1996-1998 BMW 740iL, 1997-1998 BMW 540i, 1997-1998 BMW 740i, 1999-1999 BMW 540i, 1999-1999 BMW 740i, 1999-1999 BMW 740iL
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW
Item LocatedUnited States
Quantity1
Part interchange
11531437526, 11531704324, 11531437526, 1430891, 34727, TM11105, 470-221, Z63006, 
...View more
item #1000ZPCQ
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Coolant Thermostat Housing Assembly for BMW E36 318i 1994-1999 L4 1.8L L4 1.9L
A-Premium®Part # APTHA0054
Coolant Thermostat Housing Assembly for BMW E36 318i 1994-1999 L4 1.8L L4 1.9L
4.651 Reviews
$32.99
Edit ZIP code
2-year warranty
90 days free return
Fits 1994 - 1995 BMW 318i, 1996 - 1999 BMW 318i
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW
Item LocatedUnited States
Quantity1
ColorBlack
Part interchange
11531247125, 11531432881, 11531739755, 11531739752
item #1003CVTW
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Vemo V20-99-0163 Engine Coolant Thermostat Kit
VemoPart # V20-99-0163
Vemo V20-99-0163 Engine Coolant Thermostat Kit
53 Reviews
$65.99
Quantity Less than 5
Edit ZIP code
3-year warranty
90 days free return
Fits 2002-2005 BMW 745Li, 2002-2005 BMW 745i, 2003-2007 BMW 760Li, 2004-2005 BMW 545i, 2004-2005 BMW 645Ci, 2004-2006 BMW 760i, 2004-2006 BMW X5, 2004-2006 BMW X5, 2006-2008 BMW 750Li, 2006-2008 BMW 750i, 2006-2010 BMW 550i, 2006-2010 BMW 650i, 2007-2008 BMW Alpina B7, 2007-2008 BMW X5, 2008-2008 BMW 760Li, 2008-2011 BMW X6, 2009-2009 BMW 750Li, 2009-2009 BMW 750i, 2009-2010 BMW X5, 2010-2010 BMW X5, 2010-2011 BMW 750i, 2010-2012 BMW 550i GT, 2010-2015 BMW 550i GT xDrive, 2010-2015 BMW 750Li, 2010-2015 BMW 750Li xDrive, 2010-2015 BMW 750i xDrive, 2010-2015 BMW 760Li, 2011-2012 BMW 550i, 2011-2013 BMW X5, 2011-2015 BMW 550i xDrive, 2011-2015 BMW Alpina B7, 2011-2015 BMW Alpina B7 xDrive, 2011-2015 BMW Alpina B7L, 2011-2015 BMW Alpina B7L xDrive, 2011-2017 BMW X5, 2012-2012 BMW 750i, 2012-2012 BMW M5, 2012-2012 BMW X6, 2012-2013 BMW 650i, 2012-2013 BMW 750i, 2012-2013 BMW M6, 2012-2013 BMW X6, 2012-2015 BMW 650i xDrive, 2013-2013 BMW 550i GT, 2013-2013 BMW X6, 2013-2013 BMW X6, 2013-2015 BMW 550i, 2013-2015 BMW 650i Gran Coupe, 2013-2015 BMW 650i xDrive Gran Coupe, 2013-2015 BMW M5, 2014-2014 BMW 650i, 2014-2014 BMW 650i, 2014-2014 BMW M6, 2014-2014 BMW X6, 2014-2015 BMW 550i GT, 2014-2015 BMW 750i, 2014-2015 BMW M6 Gran Coupe, 2015-2015 BMW 650i, 2015-2015 BMW Alpina B6 xDrive Gran Coupe, 2015-2015 BMW M3, 2015-2015 BMW M4, 2015-2015 BMW M6, 2015-2017 BMW X5, 2015-2017 BMW X6, 2015-2017 BMW X6, 2016-2016 BMW 550i, 2016-2016 BMW 550i GT xDrive, 2016-2016 BMW 550i xDrive, 2016-2016 BMW 650i, 2016-2016 BMW 650i Gran Coupe, 2016-2016 BMW 650i xDrive, 2016-2016 BMW 650i xDrive Gran Coupe, 2016-2016 BMW 750i, 2016-2016 BMW 750i xDrive, 2016-2016 BMW Alpina B6 xDrive Gran Coupe, 2016-2016 BMW M3, 2016-2016 BMW M4, 2016-2016 BMW M4, 2016-2016 BMW M5, 2016-2016 BMW M6, 2016-2016 BMW M6 Gran Coupe, 2017-2017 BMW 550i GT xDrive, 2017-2017 BMW 650i, 2017-2017 BMW 650i Gran Coupe, 2017-2017 BMW 650i xDrive, 2017-2017 BMW 650i xDrive Gran Coupe, 2017-2017 BMW Alpina B6 xDrive Gran Coupe, 2017-2017 BMW M3, 2017-2017 BMW M4, 2017-2017 BMW M6, 2017-2017 BMW M6 Gran Coupe
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW
Item LocatedUnited States
Quantity1
Part interchange
V20-99-0163, 606105, 902817, TM27105, 571772, 34245, 1430869, 8620242105, 
...View more
item #1000XD44
Note
With seal
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Vemo V20-99-1254 Engine Coolant Thermostat
VemoPart # V20-99-1254
Vemo V20-99-1254 Engine Coolant Thermostat
53 Reviews
$22.99
Only 1 item left in stock
Edit ZIP code
3-year warranty
90 days free return
Fits 1986-1987 BMW 325e, 1986-1987 BMW 325es, 1986-1987 BMW L7, 1986-1988 BMW 325, 1986-1988 BMW 528e, 1986-1989 BMW 535i, 1986-1989 BMW 635CSi, 1986-1989 BMW 735i, 1987-1987 BMW L6, 1987-1989 BMW 325i, 1987-1989 BMW 325is, 1988-1988 BMW 535is, 1988-1989 BMW 325iX, 1988-1989 BMW 735iL, 1989-1989 BMW 525i, 1990-1990 BMW 525i, 1990-1991 BMW 325iX, 1990-1991 BMW 325is, 1990-1992 BMW 735i, 1990-1992 BMW 735iL, 1990-1993 BMW 325i, 1990-1993 BMW 535i
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW
Item LocatedUnited States
Quantity1
Part interchange
V20-99-1254, 78254S, TX2780D, 5305380, 27479, 27480, 12188, 22680, 
...View more
item #1001QQZ8
Note
With seal
Show less
Vemo V20-99-1286 Engine Coolant Thermostat Kit
VemoPart # V20-99-1286
Vemo V20-99-1286 Engine Coolant Thermostat Kit
53 Reviews
$145.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2011-2011 BMW 135i, 2011-2011 BMW 335i, 2011-2012 BMW 335i xDrive, 2011-2013 BMW X5, 2011-2013 BMW X6, 2012-2013 BMW 135i, 2012-2013 BMW 335i, 2012-2013 BMW 335i, 2013-2013 BMW 135is, 2013-2013 BMW 335i xDrive, 2013-2013 BMW X1, 2014-2014 BMW X1, 2014-2014 BMW X6, 2015-2015 BMW X1
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW
Item LocatedUnited States
Quantity1
Part interchange
V20-99-1286, 1601479925, 11537601158, 7601158, 410766103D0
item #1000XAQY
Note
With seal
Show less
ÜRO Parts 11538671517 Engine Coolant Thermostat / Water Inlet Assembly
ÜRO PartsPart # 11538671517
ÜRO Parts 11538671517 Engine Coolant Thermostat / Water Inlet Assembly
51 Reviews
$42.99
Quantity Less than 2
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
Item LocatedUnited States
Quantity1
ColorBlack
Part interchange
11538671517, 11538671517, 11537580627, 1430919, 902-5172, 34789, TM2197, 828-207, 
...View more
item #1000ZUA7
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ÜRO Parts 11517805811 Engine Coolant Thermostat / Water Inlet Assembly
ÜRO PartsPart # 11517805811
ÜRO Parts 11517805811 Engine Coolant Thermostat / Water Inlet Assembly
51 Reviews
$37.99
Only 1 item left in stock
Edit ZIP code
3-year warranty
90 days free return
Fits 2009-2011 BMW 335d, 2009-2013 BMW X5
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW
Item LocatedUnited States
Quantity1
ColorBlack
Part interchange
11517805811, 11517805811, 11517789014, 11517787052, 1430904, 902-5822, 7.8636, 86210, 
...View more
item #1000ZPZ3
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Vemo V20-99-1253 Engine Coolant Thermostat
VemoPart # V20-99-1253
Vemo V20-99-1253 Engine Coolant Thermostat
53 Reviews
$24.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1991-1995 BMW 318i, 1991-1995 BMW 318is, 1991-1995 BMW 525i, 1992-1995 BMW 325i, 1992-1995 BMW 325is, 1995-1995 BMW 318ti, 1995-1995 BMW 320i, 1995-1999 BMW M3, 1998-2000 BMW Z3
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW
Item LocatedUnited States
Quantity1
Part interchange
V20-99-1253, 78258S, 5305388, 27488, 11444, TX2888D, 22688, 1430731, 
...View more
item #1001QRAR
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ÜRO Parts 11537549476 Engine Coolant Thermostat / Water Inlet Assembly
ÜRO PartsPart # 11537549476
ÜRO Parts 11537549476 Engine Coolant Thermostat / Water Inlet Assembly
51 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, 2008-2010 BMW 535i, 2008-2013 BMW 128i, 2009-2010 BMW 335i xDrive, 2009-2010 BMW 528i xDrive, 2009-2010 BMW 535i xDrive, 2009-2011 BMW Z4, 2009-2012 BMW 328i xDrive, 2011-2011 BMW 1 Series M, 2011-2013 BMW 335is, 2012-2012 BMW 328i, 2012-2012 BMW 328i, 2012-2013 BMW 328i, 2012-2013 BMW 328i, 2012-2013 BMW 328i, 2012-2013 BMW 328i, 2012-2013 BMW Z4, 2013-2013 BMW 328i xDrive, 2013-2013 BMW 328i xDrive, 2014-2016 BMW Z4, 2014-2016 BMW Z4
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW
Item LocatedUnited States
Quantity1
MaterialPlastic
ColorBlack
Part interchange
11537549476, 11537544788, 11537536655, 11537549476, 902-816, TM1497, 568-207, CTA0033, 
...View more
item #1000ZQ7H
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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
4.651 Reviews
$31.99
Quantity Less than 4
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
Item LocatedUnited States
Quantity1
MaterialAluminum
Part interchange
902-5007, 85068, 11531740478
item #1005EYS6
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Vemo V20-99-1307 Engine Coolant Thermostat Housing
VemoPart # V20-99-1307
Vemo V20-99-1307 Engine Coolant Thermostat Housing
53 Reviews
$352.99
Quantity Less than 4
Edit ZIP code
3-year warranty
90 days free return
Fits 2016-2017 BMW 330e, 2017-2017 BMW 430i Gran Coupe, 2017-2019 BMW 330i, 2017-2019 BMW 330i GT xDrive, 2017-2019 BMW 330i xDrive, 2017-2019 BMW 740e xDrive, 2017-2020 BMW 430i, 2017-2020 BMW 430i xDrive, 2017-2020 BMW 430i xDrive Gran Coupe, 2017-2020 BMW 530i, 2017-2020 BMW 530i xDrive, 2017-2021 BMW 230i, 2017-2021 BMW 230i xDrive, 2018-2018 BMW 330e, 2018-2019 BMW X3, 2018-2020 BMW 430i Gran Coupe, 2018-2020 BMW 530e, 2018-2020 BMW 530e xDrive, 2019-2019 BMW X3, 2019-2019 BMW X4
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW
Item LocatedUnited States
Quantity1
Part interchange
V20-99-1307, 11537644811, 7644811
item #1001QP19
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ÜRO Parts 11537586783 Engine Coolant Thermostat / Water Inlet Assembly
ÜRO PartsPart # 11537586783
ÜRO Parts 11537586783 Engine Coolant Thermostat / Water Inlet Assembly
51 Reviews
$91.99
Quantity Less than 3
Edit ZIP code
3-year warranty
90 days free return
Fits 2011-2012 BMW X3
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW
Item LocatedUnited States
Quantity1
ColorBlack
Part interchange
11537586783, 11537586783, 902-5161, 86258, 955-207, URO-017543
item #1000ZQ5K
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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.

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