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INFINITI Q45 Thermostat

6 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 2002-2006 INFINITI Q45Engine Coolant Thermostat for 2002-2006 INFINITI Q45
A-Premium®Part # APTHE001
Engine Coolant Thermostat for 2002-2006 INFINITI Q45
4.680 Reviews
$23.99
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2-year warranty
90 days free return
Fits INFINITI Q45: 2002 2003 2004 2005 2006
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Vehicle: INFINITI Q45
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1012NC2P
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Engine Coolant Thermostat for 2002-2006 INFINITI Q45
A-Premium®Part # APTHE002
Engine Coolant Thermostat for 2002-2006 INFINITI Q45
4.680 Reviews
$27.99
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2-year warranty
90 days free return
Fits INFINITI Q45: 2002 2003 2004 2005 2006
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: INFINITI Q45
Item LocatedUnited States
Quantity1
ConditionNew
item #1014GEXN
Note
Start to Open Temperature: 77℃.
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Beck/Arnley 143-0721 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0721
Beck/Arnley 143-0721 Engine Coolant Thermostat
51 Reviews
$30.99
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3-year warranty
90 days free return
Fits 1990-1992 INFINITI M30, 1993-1997 INFINITI J30, 1997-2000 INFINITI QX4, 1997-2001 INFINITI Q45, 1993-1999 Mercury Villager, 1984-1996 Nissan 300ZX, 1985-1994 Nissan Maxima, 1986-1994 Nissan D21, 1987-1988 Nissan 200SX, 1987-1988 Nissan Pathfinder, 1989-1995 Nissan Pathfinder, 1993-2002 Nissan Quest, 1995-1995 Nissan Pickup, 1996-2000 Nissan Pathfinder, 1999-2004 Nissan Frontier, 2000-2004 Nissan Xterra
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: INFINITI Q45
Item LocatedUnited States
Quantity1
Part interchange
143-0721
item #1000XETQ
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Beck/Arnley 143-0845 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0845
Beck/Arnley 143-0845 Engine Coolant Thermostat
51 Reviews
$35.99
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3-year warranty
90 days free return
Fits 1997-1999 Acura CL, 1997-2005 Acura NSX, 2000-2012 Acura RL, 2000-2014 Acura TL, 2001-2003 Acura CL, 2001-2013 Acura MDX, 2010-2013 Acura ZDX, 2010-2014 Acura TSX, 1999-2001 Honda Prelude, 1999-2017 Honda Odyssey, 2000-2009 Honda S2000, 2003-2005 Honda Accord, 2003-2015 Honda Pilot, 2006-2007 Honda Accord, 2006-2014 Honda Ridgeline, 2008-2012 Honda Accord, 2003-2004 INFINITI M45, 2003-2005 INFINITI Q45, 2003-2008 INFINITI FX45, 2004-2013 INFINITI QX56
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: INFINITI Q45
Item LocatedUnited States
Quantity1
Part interchange
143-0845
item #1000XHRU
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Engine Coolant Thermostat - Lower - Mahle TX 147 82D
MahlePart # TX 147 82D
Engine Coolant Thermostat - Lower - Mahle TX 147 82D
51 Reviews
$28.99
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3-year warranty
90 days free return
Fits 2000-2000 Chrysler Cirrus, 2000-2000 Chrysler Sebring, 2005-2005 Chrysler Sebring, 2000-2000 Dodge Avenger, 2000-2000 Dodge Stratus, 2005-2005 Dodge Stratus, 2002-2005 INFINITI Q45, 2003-2004 INFINITI M45, 2003-2008 INFINITI FX45, 2004-2013 INFINITI QX56, 2006-2006 INFINITI Q45, 2006-2010 INFINITI M45, 2009-2013 INFINITI FX50, 2011-2013 INFINITI M56, 2014-2014 INFINITI QX70, 2014-2015 INFINITI Q70, 2014-2015 INFINITI QX80, 2015-2015 INFINITI Q70L, 2003-2005 Mitsubishi Eclipse, 2003-2005 Mitsubishi Montero
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Vehicle: INFINITI Q45
Item LocatedUnited States
Quantity1
Installation PositionLower
Part interchange
TX 147 82D, 21200-AD200, 21200-AD201, 21200-1LA0A, 33878, 14128, TX14782D, 297-180, 
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item #1000XPVK
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Engine Coolant Thermostat - Upper - Mahle TX 168 95
MahlePart # TX 168 95
Engine Coolant Thermostat - Upper - Mahle TX 168 95
51 Reviews
$29.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2000-2001 INFINITI I30, 2001-2003 INFINITI QX4, 2002-2005 INFINITI Q45, 2003-2004 INFINITI M45, 2003-2008 INFINITI FX45, 2006-2006 INFINITI Q45, 2006-2010 INFINITI M45, 2000-2001 Nissan Maxima, 2001-2004 Nissan Pathfinder, 2002-2006 Nissan Sentra, 2002-2013 Nissan Altima, 2007-2008 Nissan Versa, 2007-2012 Nissan Sentra, 2008-2014 Nissan Rogue, 2009-2010 Nissan Versa, 2009-2011 Nissan Cube, 2011-2012 Nissan Juke, 2012-2012 Nissan Cube, 2013-2013 Nissan Juke, 2014-2014 Nissan Rogue Select
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: INFINITI Q45
Item LocatedUnited States
Quantity1
Installation PositionUpper
Part interchange
TX 168 95, 21230-6N20A, 34160, 15112, TX16895, 7302-180
item #1000XP8C
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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.