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Geo Thermostat

15 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 APTHE018 Engine Coolant ThermostatA-Premium APTHE018 Engine Coolant Thermostat
A-Premium®Part # APTHE018
A-Premium APTHE018 Engine Coolant Thermostat
4.692 Reviews
$17.99
Low stock: Only 5 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2008 - 2009 Ford F-650, 2008 - 2009 Ford F-750, 1999 - 2001 Toyota Solara, 1998 - 1998 Ford F-800, 1998 - 1998 Ford F-800 LPO, 1997 - 1998 Nissan 200SX, 1996 - 2000 Toyota RAV4, 1996 - 1997 Nissan Sentra, 1995 - 1995 Nissan 200SX, 1994 - 1997 Toyota Celica, 1993 - 1997 Geo Prizm, 1993 - 1997 Toyota Corolla, 1992 - 2001 Toyota Camry, 1992 - 1999 Toyota Celica, 1992 - 1999 Toyota Paseo, 1991 - 1993 Nissan NX, 1990 - 1993 Toyota Celica, 1989 - 1999 Nissan Sentra, 1989 - 1997 Geo Prizm, 1989 - 1990 Nissan Pulsar NX
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo
Item LocatedUnited States
Quantity1
MaterialMetal
ConditionNew
item #1005UU8S
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A-Premium APTHE017 Engine Coolant Thermostat
A-Premium®Part # APTHE017
A-Premium APTHE017 Engine Coolant Thermostat
4.692 Reviews
$17.99
Low stock: Only 4 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2008 - 2009 Ford F-650, 2008 - 2009 Ford F-750, 1999 - 2001 Toyota Solara, 1998 - 1998 Ford F-800, 1998 - 1998 Ford F-800 LPO, 1997 - 1998 Nissan 200SX, 1996 - 2000 Toyota RAV4, 1996 - 1997 Nissan Sentra, 1995 - 1995 Nissan 200SX, 1994 - 1997 Toyota Celica, 1993 - 1997 Geo Prizm, 1993 - 1997 Toyota Corolla, 1992 - 2001 Toyota Camry, 1992 - 1999 Toyota Celica, 1992 - 1999 Toyota Paseo, 1991 - 1993 Nissan NX, 1990 - 1993 Toyota Celica, 1989 - 1999 Nissan Sentra, 1989 - 1997 Geo Prizm, 1989 - 1990 Nissan Pulsar NX
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo
Item LocatedUnited States
Quantity1
MaterialMetal
ConditionNew
item #1005USAT
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Beck/Arnley 143-0686 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0686
Beck/Arnley 143-0686 Engine Coolant Thermostat
52 Reviews
$19.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1994-1996 Honda Passport, 1993-1993 Isuzu Stylus, 1992-1993 Geo Storm, 1992-1992 Isuzu Impulse, 1992-1992 Isuzu Stylus, 1991-1997 Isuzu Rodeo, 1991-1991 Isuzu Stylus, 1990-1994 Subaru Loyale, 1990-1991 Geo Storm, 1989-1994 Isuzu Amigo, 1989-1991 Isuzu Trooper, 1989-1989 Geo Spectrum, 1989-1989 Nissan Pulsar NX, 1988-1995 Isuzu Pickup, 1988-1995 Isuzu Pickup, 1988-1990 Isuzu Pickup, 1988-1989 Subaru GL, 1988-1988 Isuzu Trooper, 1987-1988 Nissan 200SX, 1987-1988 Nissan Van
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0686
item #1000XHZN
Show less
Beck/Arnley 143-0684 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0684
Beck/Arnley 143-0684 Engine Coolant Thermostat
52 Reviews
$20.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1995-1995 Isuzu Pickup, 1994-1996 Honda Passport, 1993-1993 Isuzu Stylus, 1992-1993 Geo Storm, 1992-1992 Isuzu Impulse, 1992-1992 Isuzu Stylus, 1991-1997 Isuzu Rodeo, 1991-1994 Isuzu Pickup, 1991-1994 Isuzu Pickup, 1991-1991 Isuzu Stylus, 1990-1994 Subaru Loyale, 1990-1991 Geo Storm, 1989-1994 Isuzu Amigo, 1989-1991 Isuzu Trooper, 1989-1989 Geo Spectrum, 1989-1989 Nissan Pulsar NX, 1988-1990 Isuzu Pickup, 1988-1989 Subaru GL, 1988-1988 Isuzu Trooper, 1987-1988 Nissan 200SX
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo
Item LocatedUnited States
Quantity1
Part interchange
143-0684
item #1000XKL4
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Beck/Arnley 143-0694 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0694
Beck/Arnley 143-0694 Engine Coolant Thermostat
52 Reviews
$21.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1999-2000 Suzuki Esteem, 1998-2000 Chevrolet Metro, 1995-1999 Suzuki Swift, 1995-1998 Suzuki Esteem, 1995-1997 Geo Metro, 1992-1994 Suzuki Swift, 1991-1994 Isuzu Pickup, 1991-1992 Isuzu Rodeo, 1989-1993 Geo Metro, 1989-1991 Suzuki Swift, 1987-1991 Subaru Justy, 1984-1991 Nissan Micra
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0694
item #1000XLD4
Show less
Beck/Arnley 143-0685 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0685
Beck/Arnley 143-0685 Engine Coolant Thermostat
52 Reviews
$19.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1994-1996 Honda Passport, 1993-1993 Isuzu Stylus, 1992-1993 Geo Storm, 1992-1992 Isuzu Impulse, 1992-1992 Isuzu Stylus, 1991-1997 Isuzu Rodeo, 1991-1991 Isuzu Stylus, 1990-1994 Subaru Loyale, 1990-1991 Geo Storm, 1989-1994 Isuzu Amigo, 1989-1991 Isuzu Trooper, 1989-1989 Geo Spectrum, 1989-1989 Nissan Pulsar NX, 1988-1995 Isuzu Pickup, 1988-1995 Isuzu Pickup, 1988-1990 Isuzu Pickup, 1988-1989 Subaru GL, 1988-1988 Isuzu Trooper, 1987-1988 Nissan 200SX, 1987-1988 Nissan Van
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo
Item LocatedUnited States
Quantity1
Part interchange
143-0685
item #1000XH1H
Show less
Beck/Arnley 143-0688 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0688
Beck/Arnley 143-0688 Engine Coolant Thermostat
52 Reviews
$27.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2001-2005 Kia Rio, 1999-1999 Chevrolet Tracker, 1999-1999 Chevrolet Tracker, 1999-1999 Chevrolet Tracker, 1998-1998 Chevrolet Tracker, 1997-1998 Mitsubishi 3000GT, 1996-1998 Suzuki X-90, 1996-1996 Mitsubishi Diamante, 1994-1997 Ford Aspire, 1994-1997 Mazda Miata, 1994-1994 Mitsubishi Montero, 1993-1996 Mitsubishi Mirage, 1992-1996 Eagle Summit, 1992-1995 Hyundai Elantra, 1992-1995 Mitsubishi Diamante, 1992-1993 Dodge Grand Caravan, 1992-1992 Eagle Summit, 1992-1992 Mitsubishi Expo, 1991-1994 Mercury Capri, 1991-1992 Hyundai Scoupe
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo
Item LocatedUnited States
Quantity1
Part interchange
143-0688
item #1000XGE3
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Beck/Arnley 143-0689 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0689
Beck/Arnley 143-0689 Engine Coolant Thermostat
52 Reviews
$23.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2007-2009 Suzuki SX4, 2003-2003 Suzuki Vitara, 2002-2007 Suzuki Aerio, 2002-2002 Suzuki Esteem, 1999-2002 Suzuki Vitara, 1999-2001 Suzuki Esteem, 1999-1999 Chevrolet Tracker, 1999-1999 Chevrolet Tracker, 1999-1999 Chevrolet Tracker, 1999-1999 Mitsubishi 3000GT, 1998-1998 Chevrolet Tracker, 1997-1998 Mitsubishi 3000GT, 1996-1998 Suzuki X-90, 1996-1996 Mitsubishi Diamante, 1994-1997 Ford Aspire, 1994-1997 Mazda Miata, 1994-1994 Mitsubishi Montero, 1993-1996 Mitsubishi Mirage, 1992-1996 Eagle Summit, 1992-1995 Hyundai Elantra
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo
Item LocatedUnited States
Quantity1
Part interchange
143-0689
item #1000XHG9
Show less
Beck/Arnley 143-0728 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0728
Beck/Arnley 143-0728 Engine Coolant Thermostat
52 Reviews
$30.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1998-1999 Toyota Celica, 1996-2000 Toyota RAV4, 1996-1999 Nissan Sentra, 1995-1998 Nissan 200SX, 1995-1995 Nissan Sentra, 1992-2001 Toyota Camry, 1992-1997 Toyota Celica, 1992-1997 Toyota Paseo, 1991-1994 Nissan Sentra, 1991-1993 Nissan NX, 1990-1991 Toyota Celica, 1990-1990 Nissan Pulsar NX, 1989-1997 Geo Prizm, 1989-1990 Nissan Sentra, 1989-1989 Nissan Pulsar NX, 1988-1991 Toyota Camry, 1987-1989 Toyota Celica, 1987-1987 Toyota Camry, 1986-1986 Toyota Camry, 1986-1986 Toyota Celica
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0728
item #1000XLL2
Show less
Beck/Arnley 143-0687 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0687
Beck/Arnley 143-0687 Engine Coolant Thermostat
52 Reviews
$22.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1999-1999 Chevrolet Tracker, 1999-1999 Chevrolet Tracker, 1999-1999 Chevrolet Tracker, 1998-1998 Chevrolet Tracker, 1997-1998 Mitsubishi 3000GT, 1996-1998 Suzuki X-90, 1996-1996 Mitsubishi Diamante, 1994-1997 Ford Aspire, 1994-1997 Mazda Miata, 1994-1994 Mitsubishi Montero, 1993-1996 Mitsubishi Mirage, 1992-1996 Eagle Summit, 1992-1995 Hyundai Elantra, 1992-1995 Mitsubishi Diamante, 1992-1994 Dodge Colt, 1992-1993 Dodge Grand Caravan, 1992-1992 Eagle Summit, 1992-1992 Mitsubishi Expo, 1991-1994 Mercury Capri, 1991-1992 Hyundai Scoupe
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0687
item #1000XKVK
Show less
Beck/Arnley 143-0697 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0697
Beck/Arnley 143-0697 Engine Coolant Thermostat
52 Reviews
$23.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1996-2000 Toyota RAV4, 1996-1999 Nissan Sentra, 1995-1999 Toyota Celica, 1995-1998 Nissan 200SX, 1995-1995 Nissan Sentra, 1992-2001 Toyota Camry, 1992-1999 Toyota Paseo, 1992-1994 Toyota Celica, 1991-1994 Nissan Sentra, 1991-1993 Nissan NX, 1990-1991 Toyota Celica, 1990-1990 Nissan Pulsar NX, 1989-1997 Geo Prizm, 1989-1990 Nissan Sentra, 1989-1989 Nissan Pulsar NX, 1988-1991 Toyota Camry, 1987-1989 Toyota Celica, 1987-1987 Toyota Camry, 1986-1986 Toyota Camry, 1986-1986 Toyota Celica
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo
Item LocatedUnited States
Quantity1
Part interchange
143-0697
item #1000XKK3
Show less
Beck/Arnley 143-0654 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0654
Beck/Arnley 143-0654 Engine Coolant Thermostat
52 Reviews
$31.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1999-2001 Toyota Solara, 1998-1999 Toyota Celica, 1996-2000 Toyota RAV4, 1996-1999 Nissan Sentra, 1995-1998 Nissan 200SX, 1995-1995 Nissan Sentra, 1992-2001 Toyota Camry, 1992-1997 Toyota Celica, 1992-1997 Toyota Paseo, 1991-1994 Nissan Sentra, 1991-1993 Nissan NX, 1990-1991 Toyota Celica, 1990-1990 Nissan Pulsar NX, 1989-1997 Geo Prizm, 1989-1990 Nissan Sentra, 1989-1989 Nissan Pulsar NX, 1988-1991 Toyota Camry, 1987-1989 Toyota Celica, 1987-1987 Toyota Camry, 1986-1986 Toyota Camry
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0654
item #1000XK4S
Show less
Beck/Arnley 143-0727 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0727
Beck/Arnley 143-0727 Engine Coolant Thermostat
52 Reviews
$22.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1999-2000 Suzuki Esteem, 1998-2000 Chevrolet Metro, 1995-2001 Suzuki Swift, 1995-1998 Suzuki Esteem, 1995-1997 Geo Metro, 1992-1994 Suzuki Swift, 1991-1994 Isuzu Pickup, 1991-1992 Isuzu Rodeo, 1990-1991 Isuzu Trooper, 1989-1993 Geo Metro, 1989-1991 Suzuki Swift, 1987-1991 Subaru Justy, 1984-1991 Nissan Micra
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0727
item #1000XGS4
Show less
Engine Coolant Thermostat - Mahle TX 7 88D
MahlePart # TX 7 88D
Engine Coolant Thermostat - Mahle TX 7 88D
51 Reviews
$23.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1998-1998 Chevrolet Tracker, 1996-2000 Ford Explorer, 1996-1998 Suzuki X-90, 1994-2000 Mazda B4000, 1991-1995 Ford Explorer, 1991-1994 Mazda Navajo, 1990-2000 Ford Ranger, 1990-1997 Ford Aerostar, 1989-1997 Geo Tracker, 1989-1991 Chevrolet Tracker, 1989-1989 Suzuki Sidekick, 1987-1990 Ford Bronco II, 1986-1995 Suzuki Samurai, 1986-1990 Ford Ranger, 1986-1986 Ford Bronco II
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo
Item LocatedUnited States
Quantity1
Part interchange
TX 7 88D, RT1161, 33199S, 13959, TX788D, 201-192JV, 17600-83841, 17600-85841, 
...View more
item #1000XLX6
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Engine Coolant Thermostat - Mahle TX 159 82
MahlePart # TX 159 82
Engine Coolant Thermostat - Mahle TX 159 82
51 Reviews
$24.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1999-2001 Toyota Solara, 1996-2000 Toyota RAV4, 1996-1999 Nissan Sentra, 1995-1998 Nissan 200SX, 1995-1995 Nissan Sentra, 1994-1999 Toyota Celica, 1993-1997 Geo Prizm, 1992-2001 Toyota Camry, 1992-1998 Toyota Paseo, 1992-1993 Toyota Celica, 1991-1994 Nissan Sentra, 1991-1993 Nissan NX, 1990-1993 Toyota Celica, 1990-1990 Nissan Pulsar NX, 1989-1990 Nissan Sentra, 1989-1989 Nissan Pulsar NX, 1988-1991 Toyota Camry, 1987-1989 Toyota Celica, 1987-1987 Toyota Camry, 1986-1997 Toyota Corolla
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo
Item LocatedUnited States
Quantity1
Part interchange
TX 159 82, 21200 77A61, 21200 77A60, 33708, 131-109, 131-110, 13758, TX15982, 
...View more
item #1000XR4E
Show less

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