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Mercury Thermostat

53 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 2006-2011 Mercury MilanEngine Coolant Thermostat Housing Assembly for 2006-2011 Mercury Milan
A-Premium®Part # APTHA0082
Engine Coolant Thermostat Housing Assembly for 2006-2011 Mercury Milan
52 Reviews
CA$27.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mercury Milan: 2006 2007 2008 2009 2010 2011
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mercury
Item LocatedCanada
ColorBlack
ConditionNew
item #1012Y5WH
Note
Engine Coolant Thermostat Housing Assembly -- Cover, Includes Thermostat.
Show less
Engine Coolant Thermostat Housing Assembly for 1999-2000 Mercury Mystique
A-Premium®Part # APTHA0007
Engine Coolant Thermostat Housing Assembly for 1999-2000 Mercury Mystique
52 Reviews
CA$59.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mercury Mystique: 1999 2000
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mercury
Item LocatedCanada
Quantity1
ColorBlack
ConditionNew
item #1003D0AE
Show less
Engine Coolant Thermostat Housing Assembly for 2005-2008 Mercury Mariner
A-Premium®Part # APTHA0034
Engine Coolant Thermostat Housing Assembly for 2005-2008 Mercury Mariner
52 Reviews
CA$39.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mercury Mariner: 2005 2006 2007 2008
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mercury
Item LocatedCanada
ColorBlack
ConditionNew
item #10047THZ
Note
This part comes with a cover and thermostat.
Show less
Engine Coolant Thermostat for 2002-2010 Mercury Mountaineer
A-Premium®Part # APTHE005
Engine Coolant Thermostat for 2002-2010 Mercury Mountaineer
52 Reviews
CA$27.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mercury Mountaineer: 2002 2003 2004 2005 2006 2007 2008 2009 2010
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mercury
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1012N8VW
Show less
Engine Coolant Thermostat Housing Assembly for 2006-2011 Mercury Mariner
A-Premium®Part # APTHA0082
Engine Coolant Thermostat Housing Assembly for 2006-2011 Mercury Mariner
52 Reviews
CA$27.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mercury Mariner: 2006 2007 2008 2009 2010 2011
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mercury
Item LocatedCanada
ColorBlack
ConditionNew
item #1012Y9AE
Note
Engine Coolant Thermostat Housing Assembly -- Cover, Includes Thermostat.
Show less
Engine Coolant Thermostat Housing Assembly for 1999-2002 Mercury Cougar
A-Premium®Part # APTHA0007
Engine Coolant Thermostat Housing Assembly for 1999-2002 Mercury Cougar
52 Reviews
CA$59.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mercury Cougar: 1999 2000 2001 2002
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mercury
Item LocatedCanada
Quantity1
ColorBlack
ConditionNew
item #1003CY3E
Show less
Engine Coolant Thermostat for 2002-2010 Mercury Mountaineer
A-Premium®Part # APTHE029
Engine Coolant Thermostat for 2002-2010 Mercury Mountaineer
52 Reviews
CA$27.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mercury Mountaineer: 2002 2003 2004 2005 2006 2007 2008 2009 2010
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mercury
Item LocatedUnited States
Quantity1
MaterialMetal
ConditionNew
item #1012NAP1
Show less
Engine Coolant Thermostat for 1992-2011 Mercury Grand Marquis
A-Premium®Part # APTHE005
Engine Coolant Thermostat for 1992-2011 Mercury Grand Marquis
52 Reviews
CA$27.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mercury Grand Marquis: 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mercury
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1012N6D4
Show less
Engine Coolant Thermostat for 2002-2010 Mercury Mountaineer
A-Premium®Part # APTHE028
Engine Coolant Thermostat for 2002-2010 Mercury Mountaineer
52 Reviews
CA$30.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mercury Mountaineer: 2002 2003 2004 2005 2006 2007 2008 2009 2010
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mercury
Item LocatedUnited States
Quantity1
MaterialMetal
ConditionNew
item #1012NPKS
Show less
Engine Coolant Thermostat for 2002-2010 Mercury Mountaineer
A-Premium®Part # APTHE038
Engine Coolant Thermostat for 2002-2010 Mercury Mountaineer
52 Reviews
CA$39.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mercury Mountaineer: 2002 2003 2004 2005 2006 2007 2008 2009 2010
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mercury
Item LocatedUnited States
Quantity1
MaterialMetal
ConditionNew
item #1012NPXE
Show less
Engine Coolant Thermostat for 1992-2011 Mercury Grand Marquis
A-Premium®Part # APTHE029
Engine Coolant Thermostat for 1992-2011 Mercury Grand Marquis
52 Reviews
CA$27.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mercury Grand Marquis: 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mercury
Item LocatedUnited States
Quantity1
MaterialMetal
ConditionNew
item #1012NHE6
Show less
Engine Coolant Thermostat for 1994-1997 Mercury Cougar
A-Premium®Part # APTHE005
Engine Coolant Thermostat for 1994-1997 Mercury Cougar
52 Reviews
CA$27.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mercury Cougar: 1994 1995 1996 1997
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mercury
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1012N59C
Show less
Engine Coolant Thermostat for 1992-2011 Mercury Grand Marquis
A-Premium®Part # APTHE028
Engine Coolant Thermostat for 1992-2011 Mercury Grand Marquis
52 Reviews
CA$30.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mercury Grand Marquis: 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mercury
Item LocatedUnited States
Quantity1
MaterialMetal
ConditionNew
item #1012NQN9
Show less
Engine Coolant Thermostat for 1992-2011 Mercury Grand Marquis
A-Premium®Part # APTHE038
Engine Coolant Thermostat for 1992-2011 Mercury Grand Marquis
52 Reviews
CA$39.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mercury Grand Marquis: 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mercury
Item LocatedUnited States
Quantity1
MaterialMetal
ConditionNew
item #1012NL4X
Show less
Engine Coolant Thermostat for 1994-1997 Mercury Cougar
A-Premium®Part # APTHE029
Engine Coolant Thermostat for 1994-1997 Mercury Cougar
52 Reviews
CA$27.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mercury Cougar: 1994 1995 1996 1997
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mercury
Item LocatedUnited States
Quantity1
MaterialMetal
ConditionNew
item #1012NAGV
Show less
Engine Coolant Thermostat for 2005-2006 Mercury Monterey
A-Premium®Part # APTHE005
Engine Coolant Thermostat for 2005-2006 Mercury Monterey
52 Reviews
CA$27.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mercury Monterey: 2005 2006
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mercury
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1012N70V
Show less
Engine Coolant Thermostat for 1994-1997 Mercury Cougar
A-Premium®Part # APTHE028
Engine Coolant Thermostat for 1994-1997 Mercury Cougar
52 Reviews
CA$30.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mercury Cougar: 1994 1995 1996 1997
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mercury
Item LocatedUnited States
Quantity1
MaterialMetal
ConditionNew
item #1012NN2H
Show less
Engine Coolant Thermostat for 1994-1997 Mercury Cougar
A-Premium®Part # APTHE038
Engine Coolant Thermostat for 1994-1997 Mercury Cougar
52 Reviews
CA$39.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mercury Cougar: 1994 1995 1996 1997
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mercury
Item LocatedUnited States
Quantity1
MaterialMetal
ConditionNew
item #1012NNXZ
Show less
Engine Coolant Thermostat for 2005-2006 Mercury Monterey
A-Premium®Part # APTHE029
Engine Coolant Thermostat for 2005-2006 Mercury Monterey
52 Reviews
CA$27.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mercury Monterey: 2005 2006
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mercury
Item LocatedUnited States
Quantity1
MaterialMetal
ConditionNew
item #1012NE85
Show less
Engine Coolant Thermostat for 2002-2010 Mercury Mountaineer
A-Premium®Part # APTHE003
Engine Coolant Thermostat for 2002-2010 Mercury Mountaineer
52 Reviews
CA$40.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits Mercury Mountaineer: 2002 2003 2004 2005 2006 2007 2008 2009 2010
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Mercury
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1012N8EL
Show less
Page 1 of 3

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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Learn why coolant boils or bubbles after you turn the engine off, how heat soak affects the cooling system, and how to diagnose leaks, trapped air, cap, thermostat, fan, water pump, or head gasket problems.

Jul 29, 2026