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Lexus LS430 Thermostat

3 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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A-Premium APTHE001 Engine Coolant ThermostatA-Premium APTHE001 Engine Coolant Thermostat
A-Premium®Part # APTHE001
A-Premium APTHE001 Engine Coolant Thermostat
4.687 Reviews
$23.99
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2-year warranty
90 days free return
Fits 1997 - 1999 Acura CL, 2001 - 2003 Acura CL, 1991 - 1995 Acura Legend, 2001 - 2006 Acura MDX, 2007 - 2013 Acura MDX, 1991 - 2005 Acura NSX, 1997 - 2005 Acura NSX, 2013 - 2015 Acura RDX, 1996 - 2008 Acura RL, 2009 - 2012 Acura RL, 1995 - 1998 Acura TL, 1996 - 2008 Acura TL, 2007 - 2014 Acura TL, 2009 - 2014 Acura TL, 2010 - 2014 Acura TSX, 1992 - 1994 Acura Vigor, 2010 - 2013 Acura ZDX, 1995 - 2000 Chrysler Cirrus, 1996 - 1996 Chrysler Sebring, 2000 - 2000 Chrysler Sebring
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Lexus LS430
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1005V2X1
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Beck/Arnley 143-0789 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0789
Beck/Arnley 143-0789 Engine Coolant Thermostat
51 Reviews
$34.99
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3-year warranty
90 days free return
Fits 1996-1997 Lexus LX450, 1997-1997 Lexus LS400, 1998-2000 Lexus GS400, 1998-2000 Lexus LS400, 1998-2000 Lexus SC400, 1998-2007 Lexus LX470, 2001-2006 Lexus LS430, 2001-2007 Lexus GS430, 2002-2010 Lexus SC430, 2003-2009 Lexus GX470, 1993-2007 Toyota Land Cruiser, 2000-2009 Toyota Tundra, 2001-2007 Toyota Sequoia, 2003-2009 Toyota 4Runner, 2008-2009 Toyota Sequoia
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Vehicle: Lexus LS430
Item LocatedUnited States
Quantity1
Part interchange
143-0789
item #1000XLEH
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Engine Coolant Thermostat - Mahle TX 148 82
MahlePart # TX 148 82
Engine Coolant Thermostat - Mahle TX 148 82
51 Reviews
$32.99
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3-year warranty
90 days free return
Fits 1997-2000 Lexus LS400, 1997-2000 Lexus SC400, 1998-2000 Lexus GS400, 1998-2007 Lexus LX470, 2001-2006 Lexus LS430, 2001-2007 Lexus GS430, 2002-2010 Lexus SC430, 2003-2009 Lexus GX470, 1992-2007 Toyota Land Cruiser, 2000-2009 Toyota Tundra, 2001-2007 Toyota Sequoia, 2003-2009 Toyota 4Runner, 2008-2009 Toyota Sequoia
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Lexus LS430
Item LocatedUnited States
Quantity1
Part interchange
TX 148 82, 33878, 14128, TX14882, 302-180, 90916-03100, 90916-03117, 90916-03138
item #1000XSGZ
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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.

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Jul 29, 2026