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Geo Tracker Oxygen Sensor

47 items

Shop best-selling oxygen sensors for Ford, Chevy, Honda, Nissan, Toyota, and more. Direct-fit O2 sensors with fast response, improved MPG, and reliable emissions performance.

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Upstream O2 Oxygen Sensor | 1-Pc Direct-Fit | A-Premium OS177Upstream O2 Oxygen Sensor | 1-Pc Direct-Fit | A-Premium OS177
A-Premium®Part # OS177
Upstream O2 Oxygen Sensor | 1-Pc Direct-Fit | A-Premium OS177
4.5618 Reviews
$31.99
Low stock: Only 4 left
Edit ZIP code
3-year warranty
90 days free return
Fits 1985 - 1985 Chevrolet Caprice, 1985 - 1985 Chevrolet El Camino, 1985 - 1985 Chevrolet Impala, 1985 - 1985 Chevrolet Monte Carlo, 1990 - 1991 GEO Storm, 1991 - 1993 GEO Tracker, 1994 - 1995 GEO Tracker, 1985 - 1985 GMC Caballero, 1994 - 1995 Honda Passport, 1993 - 1994 Isuzu Amigo, 1990 - 1992 Isuzu Impulse, 1995 - 1995 Isuzu Pickup, 1993 - 1993 Isuzu Pickup, 1994 - 1995 Isuzu Pickup, 1993 - 1995 Isuzu Rodeo, 1991 - 1991 Isuzu Stylus, 1985 - 1985 Pontiac Parisienne, 1991 - 1991 Suzuki Sidekick, 1992 - 1993 Suzuki Sidekick, 1994 - 1995 Suzuki Sidekick
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo Tracker
Quantity1
Installation PositionUpstream
Item LocatedUnited States
ConditionNew
item #100304G8
Show less
Downstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Heated | A-Premium APOS0277
A-Premium®Part # APOS0277
Downstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Heated | A-Premium APOS0277
4.5618 Reviews
$37.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1998 - 1998 Chevrolet Tracker, 1999 - 2000 Chevrolet Tracker, 1999 - 2000 Chevrolet Tracker, 1996 - 1997 Geo Tracker
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo Tracker
Installation PositionDownstream
Item LocatedUnited States
ConditionNew
item #10030QE4
Note
For 1999-2000 Chevrolet Tracker, this item fits Model with Non Calif-ESV.
Show less
Upstream & Downstream O2 Oxygen Sensor | 2-Pc Direct-Fit | Heated | A-Premium APOS1521
A-Premium®Part # APOS1521
Upstream & Downstream O2 Oxygen Sensor | 2-Pc Direct-Fit | Heated | A-Premium APOS1521
4.5618 Reviews
$71.99
Low stock: Only 3 left
Edit ZIP code
3-year warranty
90 days free return
Fits 1998 - 1998 Chevrolet Tracker, 1999 - 2000 Chevrolet Tracker, 1999 - 2000 Chevrolet Tracker, 1996 - 1997 Geo Tracker
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo Tracker
Installation PositionUpstream & Downstream
Item LocatedUnited States
ConditionNew
item #10049KNN
Note
This item fit for 1999-2000 model with Non Calif-ESV.
Show less
Downstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Heated | A-Premium APOS0327
A-Premium®Part # APOS0327
Downstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Heated | A-Premium APOS0327
4.5618 Reviews
$26.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1998 - 2000 Chevrolet Metro, 1998 - 2001 Chevrolet Metro, 1999 - 2000 Chevrolet Tracker, 1999 - 2000 Chevrolet Tracker, 1996 - 1997 Geo Metro, 1996 - 1997 Geo Metro, 1996 - 2001 Suzuki Swift, 1999 - 2000 Suzuki Vitara, 1999 - 2000 Suzuki Vitara
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo Tracker
Installation PositionDownstream
Item LocatedUnited States
ConditionNew
item #10030SN7
Note
Oxygen Senor - B1S2 Indicates Bank 1 Sensor 2.
For Chevrolet Tracker & Suzuki Vitara Model with California Emissions, Not Federal Emissions.
Show less
O2 Oxygen Sensor | 1-Pc Direct-Fit | Heated | A-Premium APOS0668
A-Premium®Part # APOS0668
O2 Oxygen Sensor | 1-Pc Direct-Fit | Heated | A-Premium APOS0668
4.5618 Reviews
$35.99
Low stock: Only 3 left
Edit ZIP code
3-year warranty
90 days free return
Fits 1998 - 2000 Chevrolet Metro, 1998 - 2001 Chevrolet Metro, 1998 - 2000 Chevrolet Tracker, 1999 - 2000 Chevrolet Tracker, 1994 - 1997 Geo Metro, 1995 - 1997 Geo Metro, 1994 - 1995 Geo Tracker, 1996 - 1997 Geo Tracker, 1995 - 1998 Suzuki Esteem, 1999 - 1999 Suzuki Esteem, 2000 - 2000 Suzuki Esteem, 1993 - 1995 Suzuki Sidekick, 1996 - 1998 Suzuki Sidekick, 1995 - 2001 Suzuki Swift, 1999 - 2000 Suzuki Vitara, 1999 - 2000 Suzuki Vitara, 1996 - 1998 Suzuki X-90
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo Tracker
Installation PositionCheck the fitment chart
Item LocatedUnited States
ConditionNew
item #10030TGY
Note
Oxygen Senor - B1S1 Indicates Bank 1 Sensor 1, B1S2 Indicates Bank 1 Sensor 2.
Show less
Upstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Aisin OXSAZ-00224
AisinPart # OXSAZ-00224
Upstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Aisin OXSAZ-00224
4.5618 Reviews
$43.99
Low stock: Only 2 left
Edit ZIP code
3-year warranty
90 days free return
Fits 1985 - 1985 Chevrolet Caprice, 1985 - 1985 Chevrolet El Camino, 1985 - 1985 Chevrolet Impala, 1985 - 1985 Chevrolet Monte Carlo, 1993 - 1994 Isuzu Amigo, 1990 - 1992 Isuzu Impulse, 1995 - 1995 Isuzu Pickup, 1993 - 1995 Isuzu Pickup, 1993 - 1993 Isuzu Rodeo, 1994 - 1995 Isuzu Rodeo, 1991 - 1991 Isuzu Stylus, 1990 - 1991 Geo Storm, 1991 - 1995 Geo Tracker, 1985 - 1985 GMC Caballero, 1994 - 1995 Honda Passport, 1985 - 1985 Pontiac Parisienne, 1991 - 1995 Suzuki Sidekick
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo Tracker
Quantity1
Installation PositionUpstream
Item LocatedUnited States
ConditionNew
item #1018EDR8
Show less
Downstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Aisin OXSAZ-00292
AisinPart # OXSAZ-00292
Downstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Aisin OXSAZ-00292
4.5618 Reviews
$43.99
Low stock: Only 4 left
Edit ZIP code
3-year warranty
90 days free return
Fits 1998 - 2000 Chevrolet Metro, 1998 - 2001 Chevrolet Metro, 1999 - 2000 Chevrolet Tracker, 1996 - 2001 Suzuki Swift, 1999 - 2000 Suzuki Vitara, 1996 - 1997 Geo Metro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo Tracker
Quantity1
Installation PositionDownstream
Item LocatedUnited States
ConditionNew
item #1018EAS0
Show less
Downstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Aisin OXSAZ-00276
AisinPart # OXSAZ-00276
Downstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Aisin OXSAZ-00276
4.5618 Reviews
$43.99
Low stock: Only 4 left
Edit ZIP code
3-year warranty
90 days free return
Fits 1998 - 2000 Chevrolet Tracker, 1996 - 1997 Geo Tracker
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo Tracker
Quantity1
Installation PositionDownstream
Item LocatedUnited States
ConditionNew
item #1018EDYX
Show less
Oxygen Sensor - Bosch 11027
BoschPart # 11027
Oxygen Sensor - Bosch 11027
46 Reviews
$49.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1995-1996 AM General Hummer, 1986-1990 Acura Legend, 1986-1991 Acura Integra, 1981-1982 Alfa Romeo GTV-6, 1982-1985 Alfa Romeo Spider, 1988-1988 American Motors Eagle, 1978-1978 Audi 5000, 1979-1979 Audi Fox, 1979-1985 Audi 5000, 1980-1981 Audi 4000, 1981-1986 Audi Coupe, 1982-1983 Audi 4000, 1982-1983 Audi 4000, 1983-1986 Audi Quattro, 1984-1984 Audi 4000, 1984-1987 Audi 4000 Quattro, 1985-1985 Audi 5000, 1985-1986 Audi 4000, 1986-1986 Audi 5000, 1987-1987 Audi 5000
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo Tracker
Quantity1
Item LocatedUnited States
Part interchange
11027, J3240083, 3238765, 91160612300, 94460613300, 0025421218
item #1002AYHA
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Upstream or Downstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Aisin OXSAZ-01004
AisinPart # OXSAZ-01004
Upstream or Downstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Aisin OXSAZ-01004
4.5618 Reviews
$43.99
Low stock: Only 4 left
Edit ZIP code
3-year warranty
90 days free return
Fits 1995 - 2000 Suzuki Esteem, 1993 - 1995 Suzuki Sidekick, 1996 - 1998 Suzuki Sidekick, 1995 - 2001 Suzuki Swift, 1999 - 2000 Suzuki Vitara, 1996 - 1998 Suzuki X-90, 1998 - 2000 Chevrolet Metro, 1998 - 2001 Chevrolet Metro, 1998 - 2000 Chevrolet Tracker, 1999 - 2000 Chevrolet Tracker, 1994 - 1997 Geo Metro, 1995 - 1997 Geo Metro, 1994 - 1997 Geo Tracker
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo Tracker
Quantity1
Installation PositionUpstream or Downstream
Item LocatedUnited States
ConditionNew
item #1018EHSV
Show less
Oxygen Sensor - Upstream - Denso 234-3004
DensoPart # 234-3004
Oxygen Sensor - Upstream - Denso 234-3004
4.29 Reviews
$61.99
Low stock: Only 5 left
Edit ZIP code
3-year warranty
90 days free return
Fits 1992-1992 Asuna Sunrunner, 1993-1993 Asuna Sunrunner, 1991-1991 Chevrolet Tracker, 1991-1991 GMC Tracker, 1991-1992 Geo Tracker, 1993-1994 Geo Tracker, 1994-1994 Pontiac Sunrunner
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo Tracker
Quantity1
Installation PositionUpstream
Item LocatedUnited States
Part interchange
234-3004, 21541, AFS48, 213-1230, 213-634, OS129, 15701, 19178951, 
...View more
item #1002HNCX
Show less
Spectra Premium OS5204 Oxygen Sensor
Spectra PremiumPart # OS5204
Spectra Premium OS5204 Oxygen Sensor
4.45 Reviews
$26.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1993-1993 Asuna Sunrunner, 1998-1998 Chevrolet Tracker, 1993-1995 Geo Tracker, 1996-1997 Geo Tracker, 1994-1995 Pontiac Sunrunner, 1996-1997 Pontiac Sunrunner, 1993-1993 Suzuki Sidekick, 1994-1995 Suzuki Sidekick, 1995-1999 Suzuki Esteem, 1996-1998 Suzuki Sidekick, 1996-1998 Suzuki X-90, 2000-2000 Suzuki Esteem, 2000-2001 Suzuki Esteem, 2000-2002 Suzuki Esteem, 2000-2002 Suzuki Esteem
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo Tracker
Quantity1
Item LocatedUnited States
Part interchange
OS5204, 751825, 753446, 753451, SG322T, SG322, 2131362, 213404, 
...View more
item #1000YPDS
Show less
Denso 234-4060 Oxygen Sensor, Upstream
DensoPart # 234-4060
Denso 234-4060 Oxygen Sensor, Upstream
4.29 Reviews
$88.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1993-1993 Asuna Sunrunner, 1998-1998 Chevrolet Tracker, 1993-1995 Geo Tracker, 1996-1997 Geo Tracker, 1994-1995 Pontiac Sunrunner, 1996-1997 Pontiac Sunrunner, 1992-1993 Suzuki Sidekick, 1994-1995 Suzuki Sidekick, 1995-2000 Suzuki Esteem, 1996-1998 Suzuki Sidekick, 1996-1998 Suzuki X-90, 2001-2001 Suzuki Esteem, 2002-2002 Suzuki Esteem
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo Tracker
Quantity1
Installation PositionUpstream
Item LocatedUnited States
Part interchange
234-4060, 1821358B11, 1821358B21, 1821358B00, 1821358B20, 1821358B10, 24617, 21508, 
...View more
item #1003S4X7
Show less
Spectra Premium OS5206 Oxygen Sensor, Downstream
Spectra PremiumPart # OS5206
Spectra Premium OS5206 Oxygen Sensor, Downstream
4.45 Reviews
$25.99
Low stock: Only 3 left
Edit ZIP code
3-year warranty
90 days free return
Fits 1998-2001 Chevrolet Metro, 1999-2000 Chevrolet Tracker, 1996-1997 Geo Metro, 1996-2000 Pontiac Firefly, 1996-2001 Suzuki Swift, 1999-2000 Suzuki Vitara
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo Tracker
Quantity1
Installation PositionDownstream
Item LocatedUnited States
Part interchange
OS5206, 751769, 752023, SG567, SG324, SG567T, SG324T, 2134282, 
...View more
item #1000YHUA
Show less
Oxygen Sensor - Upstream - Denso 234-4049
DensoPart # 234-4049
Oxygen Sensor - Upstream - Denso 234-4049
4.29 Reviews
$78.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1998-2001 Chevrolet Metro, 1999-2000 Chevrolet Tracker, 1994-1994 Geo Metro, 1995-1997 Geo Metro, 1994-1994 Pontiac Firefly, 1995-2000 Pontiac Firefly, 1994-1994 Suzuki Swift, 1995-2001 Suzuki Swift, 1999-2000 Suzuki Vitara
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo Tracker
Quantity1
Installation PositionUpstream
Item LocatedUnited States
Part interchange
234-4049, 1821365D02, 1821365D01, 1821350G01, 1821350G00, 21527, 213-3078, 213-3912, 
...View more
item #1003S1DW
Show less
Oxygen Sensor - Denso 234-3000
DensoPart # 234-3000
Oxygen Sensor - Denso 234-3000
4.29 Reviews
$53.99
Low stock: Only 3 left
Edit ZIP code
3-year warranty
90 days free return
Fits 1983-1986 Alfa Romeo GTV-6, 1986-1994 Alfa Romeo Spider, 1987-1989 Alfa Romeo Milano, 1991-1993 Alfa Romeo 164, 1992-1992 Asuna Sunrunner, 1993-1993 Asuna Sunrunner, 1986-1987 Audi 5000, 1986-1988 Audi 5000 Quattro, 1987-1987 Audi 5000, 1987-1987 Audi Coupe, 1988-1988 Audi 5000, 1988-1991 Audi 90, 1988-1992 Audi 80, 1988-1992 Audi 80 Quattro, 1988-1992 Audi 90 Quattro, 1989-1991 Audi 100 Quattro, 1989-1991 Audi 200, 1989-1991 Audi 200 Quattro, 1989-1992 Audi 100, 1990-1991 Audi Coupe Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo Tracker
Quantity1
Item LocatedUnited States
Part interchange
234-3000, 213-1241, 213-1242, OS516, OS521, 13589, 13936, 13508, 
...View more
item #1002HP48
Show less
Walker Products 250-23004 Oxygen Sensor, Upstream
Walker ProductsPart # 250-23004
Walker Products 250-23004 Oxygen Sensor, Upstream
55 Reviews
$60.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1985-1985 Chevrolet Caprice, 1985-1985 Chevrolet El Camino, 1985-1985 Chevrolet Impala, 1985-1985 Chevrolet Monte Carlo, 1985-1985 GMC Caballero, 1990-1991 Geo Storm, 1991-1993 Geo Tracker, 1994-1995 Geo Tracker, 1994-1995 Honda Passport, 1990-1991 Isuzu Impulse, 1991-1991 Isuzu Stylus, 1992-1992 Isuzu Impulse, 1993-1993 Isuzu Amigo, 1993-1993 Isuzu Pickup, 1993-1993 Isuzu Rodeo, 1994-1994 Isuzu Amigo, 1994-1994 Isuzu Pickup, 1994-1994 Isuzu Rodeo, 1995-1995 Isuzu Pickup, 1995-1995 Isuzu Rodeo
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo Tracker
Quantity1
Installation PositionUpstream
Item LocatedUnited States
Part interchange
250-23004
item #1001PC72
Show less
Oxygen Sensor - Upstream - Denso 234-3014
DensoPart # 234-3014
Oxygen Sensor - Upstream - Denso 234-3014
4.29 Reviews
$62.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1990-1991 Geo Storm, 1995-1995 Geo Tracker, 1990-1991 Isuzu Impulse, 1991-1991 Isuzu Stylus, 1992-1992 Isuzu Impulse, 1995-1995 Pontiac Sunrunner, 1991-1991 Suzuki Sidekick, 1992-1993 Suzuki Sidekick, 1994-1995 Suzuki Sidekick
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo Tracker
Quantity1
Installation PositionUpstream
Item LocatedUnited States
Part interchange
234-3014, 1821356B00, 21541, 8970185870, OS129, OS102, OS1823, 213-1280, 
...View more
item #1003RX31
Show less
Bosch 15701 Oxygen Sensor, Upstream
BoschPart # 15701
Bosch 15701 Oxygen Sensor, Upstream
46 Reviews
$63.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1985-1985 Chevrolet Caprice, 1985-1985 Chevrolet El Camino, 1985-1985 Chevrolet Impala, 1985-1985 Chevrolet Monte Carlo, 1991-1991 Chevrolet Tracker, 1985-1985 GMC Caballero, 1991-1991 GMC Tracker, 1990-1991 Geo Storm, 1991-1993 Geo Tracker, 1994-1995 Geo Tracker, 1994-1995 Honda Passport, 1990-1991 Isuzu Impulse, 1991-1991 Isuzu Stylus, 1992-1992 Isuzu Impulse, 1993-1993 Isuzu Amigo, 1993-1993 Isuzu Pickup, 1993-1993 Isuzu Rodeo, 1994-1994 Isuzu Amigo, 1994-1994 Isuzu Pickup, 1994-1994 Isuzu Rodeo
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo Tracker
Quantity1
Installation PositionUpstream
Item LocatedUnited States
Part interchange
15701, 19178951, 1821356B00, 25132169, 25161530, 8990793, 97018587, 8970622920, 
...View more
item #1002DWT5
Show less
Oxygen Sensor - Downstream - Bosch 13035
BoschPart # 13035
Oxygen Sensor - Downstream - Bosch 13035
46 Reviews
$117.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1998-1998 Chevrolet Tracker, 1999-2000 Chevrolet Tracker, 1999-2000 Chevrolet Tracker, 1999-2000 Chevrolet Tracker, 2001-2001 Chevrolet Tracker, 1996-1997 Geo Tracker, 1996-1997 Pontiac Sunrunner, 1996-1998 Suzuki Sidekick, 1996-1998 Suzuki X-90, 1999-2000 Suzuki Vitara, 2002-2002 Suzuki Esteem, 2002-2007 Suzuki Aerio
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Geo Tracker
Quantity1
Installation PositionDownstream
Item LocatedUnited States
Part interchange
13035, 30028571, 1821358B41, 1821377E11
item #1002C5TS
Show less
Page 1 of 3

Your vehicle’s oxygen sensor (also known as O2 sensors) plays a critical role in engine performance, fuel efficiency, and emissions control. By continuously measuring the amount of unburned oxygen in the exhaust, the oxygen sensor sends real-time feedback to your engine control unit (ECU), ensuring the perfect air-fuel mixture.

When an oxygen sensor fails, your engine essentially runs “blind,” leading to poor fuel economy, rough idling, reduced performance, and a persistent check engine light. A timely front oxygen sensor replacement or replacement of a faulty upstream oxygen sensor or downstream oxygen sensor can restore optimal driving conditions and help you pass emissions tests with ease.

 

Why Choose A-Premium Oxygen Sensors?

Unlike universal parts that require cutting and splicing wires, A-Premium O2 sensors are engineered for direct plug-and-play installation.

  • OEM-style connectors for seamless fit
  • Pre-coated anti-seize threads for easy installation
  • Laser-welded body construction for durability
  • High-temperature sintered coating for long service life
  • Premium insulation sheathing and impact-resistant design
  • Slotted guard tube for sensor protection
  • High heat dissipation structure for extreme environments

 

Advanced Performance & Precision

A-Premium oxygen sensor technology ensures fast, accurate, and stable performance:

Performance & Response

  • ≤200ms fast response time
  • High-efficiency oxygen sensing
  • Zirconia sensing element
  • Real-time signal feedback

Precision & Control

  • Real-time exhaust tracking
  • Accurate combustion control
  • Stable signal output

Efficiency & Engine Benefits

  • Improved fuel efficiency
  • Enhanced engine performance
  • Reduced harmful emissions
  • Extended engine lifespan

Environmental Adaptability

  • Operating range: -40°F to 266°F
  • Air-tight sealing design
  • Stable performance under harsh conditions

 

3 Symptoms of a Bad Oxygen Sensor

Because O2 sensors operate in extreme heat and carbon-rich environments, they naturally degrade over time.

  • Check Engine Light (CEL): Common codes include P0135, P0171, and P0420. These often point to issues with an upstream oxygen sensor or oxygen sensor bank 1.
  • Poor Fuel Economy: A faulty oxygen sensor may cause a rich fuel mixture, dramatically lowering MPG. 20-40% worse fuel economy overnight.
  • Rough Idle & Stalling: Incorrect readings from your downstream oxygen sensor or upstream sensor can disrupt engine stability.
  • Rotten egg smell: Catalytic converter overheating from bad fuel mixture

 

Understanding O2 Sensor Positions: Upstream vs Downstream

Modern vehicles may have multiple oxygen sensor units, making it essential to identify the correct one:

  • Oxygen Sensor Bank 1vs Bank 2 
    • oxygen sensor bank 1 refers to the side of the engine with Cylinder #1
    • Bank 2 is the opposite side
  • Upstream Oxygen Sensor(Sensor 1) 
    • Located before the catalytic converter
    • Controls air-fuel ratio
    • Most common need for front oxygen sensor replacement
  • Downstream Oxygen Sensor(Sensor 2) 
    • Located after the catalytic converter
    • Monitors emissions system efficiency

Tip: Always match your diagnostic code to the correct upstream oxygen sensor or downstream oxygen sensor before purchasing.

 

Complete Your Emissions Repair

Replacing your oxygen sensor is often part of a larger emissions system fix. Consider inspecting these related components:

 

Shop by Popular Makes

To help you quickly find the right oxygen sensor, explore our most popular vehicle-specific options:

Browse our most searched and best-selling vehicle-specific oxygen sensor options to quickly locate the right fit for your car.

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Aug 25, 2026

What Are the Symptoms of a Bad Oxygen Sensor?

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