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Audi A6 Quattro Oxygen Sensors

197 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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1-Pc O2 Oxygen Sensor A-Premium APOS18551-Pc O2 Oxygen Sensor A-Premium APOS1855
A-Premium®Part # APOS1855
1-Pc O2 Oxygen Sensor A-Premium APOS1855
4.5667 Reviews
$29.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 1996 - 1997 Audi A6, 1995 - 1997 Audi A6 Quattro, 1995 - 1995 Audi A6, 1994 - 1998 Audi Cabriolet, 1994 - 1995 Audi 90 Quattro, 1994 - 1994 Audi 100, 1994 - 1994 Audi 100 Quattro, 1993 - 1995 Audi 90, 1993 - 1993 Audi 100, 1993 - 1993 Audi 100 Quattro, 1993 - 1993 Audi 90 Quattro, 1988 - 1988 Ferrari Mondial 3.2, 1988 - 1988 Saab 900, 1988 - 1988 Volvo 244, 1988 - 1988 Volvo 245, 1987 - 1989 Saab 9000, 1986 - 1989 Ferrari 328 GTS, 1985 - 1988 Volvo 740, 1985 - 1986 Volvo 740, 1985 - 1985 Volvo 244
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A6 Quattro
Installation PositionCheck the fitment chart
Item LocatedUnited States
ConditionNew
item #10026A8Q
Note
O2 Sensor - Bank 1 Sensor 1 (B1S1).
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Downstream Driver & Upstream Passenger O2 Oxygen Sensor | 2-Pc Direct-Fit | A-Premium APOS1572
A-Premium®Part # APOS1572
Downstream Driver & Upstream Passenger O2 Oxygen Sensor | 2-Pc Direct-Fit | A-Premium APOS1572
4.5667 Reviews
$82.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2011 - 2011 Audi A6 Quattro, 2010 - 2011 Audi A6, 2009 - 2009 Audi A6 Quattro, 2005 - 2005 Audi A6 Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A6 Quattro
Quantity2
Installation PositionDownstream Driver & Upstream Passenger
Item LocatedUnited States
ConditionNew
item #10049R76
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Upstream & Downstream O2 Oxygen Sensor | 2-Pc Direct-Fit | A-Premium APOS0888
A-Premium®Part # APOS0888
Upstream & Downstream O2 Oxygen Sensor | 2-Pc Direct-Fit | A-Premium APOS0888
4.5667 Reviews
$86.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2013 - 2016 Audi allroad, 2013 - 2015 Audi A6 Quattro, 2012 - 2015 Audi A6, 2011 - 2017 Audi Q5, 2011 - 2017 Audi Q5, 2010 - 2017 Audi A5 Quattro, 2010 - 2014 Audi A5, 2009 - 2016 Audi A4, 2009 - 2016 Audi A4 Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A6 Quattro
Installation PositionUpstream & Downstream
Item LocatedUnited States
ConditionNew
item #1001GN7G
Note
O2 Sensor - B1S1, B1S2.
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Upstream & Downstream O2 Oxygen Sensor | 4-Pc Direct-Fit | A-Premium APOS1969
A-Premium®Part # APOS1969
Upstream & Downstream O2 Oxygen Sensor | 4-Pc Direct-Fit | A-Premium APOS1969
4.5667 Reviews
$126.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2005 - 2006 Audi A4 Quattro, 2005 - 2005 Audi A4, 2002 - 2005 Audi Allroad Quattro, 2002 - 2004 Audi A6 Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A6 Quattro
Quantity4
Installation PositionUpstream & Downstream
Item LocatedUnited States
ConditionNew
item #10049SLS
Show less
Upstream O2 Oxygen Sensor | 2-Pc Direct-Fit | Heated | A-Premium APOS0397
A-Premium®Part # APOS0397
Upstream O2 Oxygen Sensor | 2-Pc Direct-Fit | Heated | A-Premium APOS0397
4.5667 Reviews
$48.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2002 - 2003 Audi S6, 2001 - 2001 Audi Allroad Quattro, 2000 - 2005 Volkswagen Passat, 2000 - 2004 Audi A6 Quattro, 2000 - 2002 Audi S4, 2000 - 2001 Audi A4, 2000 - 2001 Audi A4 Quattro, 2000 - 2001 Audi A6, 2000 - 2001 Audi A6 Quattro, 2000 - 2001 Audi A6 Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A6 Quattro
Quantity2
Installation PositionUpstream
Item LocatedUnited States
ConditionNew
item #10049W6P
Show less
Upstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Heated | A-Premium APOS0437
A-Premium®Part # APOS0437
Upstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Heated | A-Premium APOS0437
4.5667 Reviews
$63.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2024 - 2024 Hyundai Elantra, 2022 - 2023 Hyundai Elantra, 2022 - 2022 Hyundai Ioniq, 2021 - 2022 Kia Niro, 2021 - 2021 Hyundai Elantra, 2018 - 2019 Hyundai Accent, 2018 - 2019 Kia Rio, 2017 - 2021 Hyundai Ioniq, 2017 - 2020 Kia Niro, 2017 - 2019 Audi Q7, 2017 - 2019 Kia Soul, 2017 - 2018 Audi A7 Quattro, 2017 - 2018 Audi A8 Quattro, 2016 - 2018 Audi A3 Sportback e-tron, 2016 - 2016 Fiat 500L, 2015 - 2018 Audi A6 Quattro, 2015 - 2017 Audi Q5, 2015 - 2017 Audi S5, 2015 - 2017 Audi SQ5, 2015 - 2017 Fiat 500
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A6 Quattro
Installation PositionUpstream
Item LocatedUnited States
ConditionNew
item #100323QG
Note
Oxygen Senor - B1S1 Indicates Bank 1 Sensor 1. B2S1 Indicates Bank 2 Sensor 1.
【Note-1】For 2011 Hyundai Sonata L4 2.0L, it fits the model built To 01/25/2011.
【Note-2】For 2009 Hyundai Elantra, it fits the model built From 04/03/2009.
【Note-3】For 2010 Hyundai Elantra, it fits Sedan only, not Hatchback.
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Upstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Heated | A-Premium APOS0743
A-Premium®Part # APOS0743
Upstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Heated | A-Premium APOS0743
4.5667 Reviews
$48.99
Low stock: Only 3 left
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2021 - 2021 Audi A7 Sportback, 2020 - 2021 Audi Q5 PHEV, 2020 - 2020 Audi Q5, 2019 - 2020 Audi A6 Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A6 Quattro
Installation PositionUpstream
Item LocatedUnited States
ConditionNew
item #10032AG3
Note
O2 Sensor - B1S1 Indicates Bank 1 Sensor 1.
This item for 2019-2020 Audi A6 Quattro models built From 09/17/2018.
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Upstream O2 Oxygen Sensor | 2-Pc Direct-Fit | Heated | A-Premium APOS0824
A-Premium®Part # APOS0824
Upstream O2 Oxygen Sensor | 2-Pc Direct-Fit | Heated | A-Premium APOS0824
4.5667 Reviews
$96.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2007 - 2008 Audi RS4, 2005 - 2011 Audi A6 Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A6 Quattro
Quantity2
Installation PositionUpstream
Item LocatedUnited States
ConditionNew
item #10049YPK
Show less
Downstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Heated | A-Premium OS059
A-Premium®Part # OS059
Downstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Heated | A-Premium OS059
4.5667 Reviews
$33.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2003 - 2004 Audi RS6, 2002 - 2003 Audi S6, 2002 - 2003 Audi S8, 2001 - 2004 Audi A6 Quattro, 2001 - 2001 Audi Allroad Quattro, 2001 - 2001 Audi S8, 2000 - 2005 Volkswagen Passat, 2000 - 2003 Audi A8 Quattro, 2000 - 2002 Audi S4, 2000 - 2001 Audi A4, 2000 - 2001 Audi A4 Quattro, 2000 - 2001 Audi A6, 2000 - 2001 Audi A6 Quattro, 2000 - 2001 Audi A6 Quattro, 2000 - 2000 Audi A6 Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A6 Quattro
Quantity1
Installation PositionDownstream
Item LocatedUnited States
ConditionNew
item #10031378
Show less
Upstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Heated | A-Premium APOS0630
A-Premium®Part # APOS0630
Upstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Heated | A-Premium APOS0630
4.5667 Reviews
$48.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2019 - 2019 Audi Q7, 2019 - 2019 Audi Q7, 2019 - 2019 Audi Q7, 2019 - 2019 Audi Q7, 2019 - 2019 Audi Q7, 2019 - 2019 Audi Q7, 2019 - 2019 Kia Soul, 2019 - 2019 Kia Soul, 2018 - 2019 Hyundai Accent, 2018 - 2019 Kia Rio, 2017 - 2018 Audi Q7, 2017 - 2017 Kia Rio, 2016 - 2018 Audi A3 Sportback e-tron, 2016 - 2018 Audi A6 Quattro, 2016 - 2018 Audi A7 Quattro, 2015 - 2018 Audi A8 Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A6 Quattro
Installation PositionUpstream
Item LocatedUnited States
ConditionNew
item #10032DXK
Note
【Note-1】 For 2017 Kia Rio, it only fits for Vehicles Built in Mexico.
【Note-2】 For 2019 Kia Soul, it fits for Naturally Aspirated, not Turbocharged.
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Downstream O2 Oxygen Sensor | 1-Pc Direct-Fit | A-Premium APOS0273
A-Premium®Part # APOS0273
Downstream O2 Oxygen Sensor | 1-Pc Direct-Fit | A-Premium APOS0273
4.5667 Reviews
$26.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 1998 - 2000 Volkswagen Passat, 1998 - 1999 Audi A4 Quattro, 1998 - 1999 Audi A6, 1998 - 1999 Audi A6 Quattro, 1998 - 1998 Audi A6 Quattro, 1997 - 1999 Audi A4, 1996 - 1997 Audi A4, 1996 - 1997 Audi A4 Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A6 Quattro
Quantity1
Installation PositionDownstream
Item LocatedUnited States
ConditionNew
item #10030ND6
Show less
Downstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Heated | A-Premium APOS1875
A-Premium®Part # APOS1875
Downstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Heated | A-Premium APOS1875
4.5667 Reviews
$39.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2017 - 2018 Porsche Macan, 2016 - 2017 Audi A6, 2016 - 2016 Audi A6 Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A6 Quattro
Quantity1
Installation PositionDownstream
Item LocatedUnited States
ConditionNew
item #1000TUAU
Show less
Downstream O2 Oxygen Sensor | 2-Pc Direct-Fit | Heated | A-Premium APOS0418
A-Premium®Part # APOS0418
Downstream O2 Oxygen Sensor | 2-Pc Direct-Fit | Heated | A-Premium APOS0418
4.5667 Reviews
$46.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2015 - 2017 Audi Q5, 2015 - 2017 Audi S5, 2015 - 2017 Audi SQ5, 2015 - 2016 Audi S4, 2015 - 2015 Audi A6 Quattro, 2015 - 2015 Audi A7 Quattro, 2014 - 2014 Audi SQ5, 2013 - 2014 Audi A8 Quattro, 2012 - 2014 Audi A6 Quattro, 2012 - 2014 Audi A7 Quattro, 2010 - 2014 Audi S4, 2010 - 2014 Audi S5, 2009 - 2014 Audi Q5, 2009 - 2009 Audi A4 Quattro, 2008 - 2010 Audi A5 Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A6 Quattro
Installation PositionDownstream
Item LocatedUnited States
ConditionNew
item #10049VL5
Note
Oxygen Senor - B1S2 Indicates Bank 1 Sensor 2, B2S2 Indicates Bank 2 Sensor 2.
For Audi 2012-2015 A6 Quattro & A7 Quattro & 2013-2014 A8 Quattro & 2009-2017 Audi Q5, it fits GAS only, not fit with DIESEL.
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Upstream Driver & Passenger O2 Oxygen Sensor | 2-Pc Direct-Fit | Heated | A-Premium APOS1021
A-Premium®Part # APOS1021
Upstream Driver & Passenger O2 Oxygen Sensor | 2-Pc Direct-Fit | Heated | A-Premium APOS1021
4.5667 Reviews
$120.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2004 - 2009 Audi S4, 2004 - 2005 Audi Allroad Quattro, 2002 - 2006 Audi A4 Quattro, 2002 - 2005 Audi A4, 2002 - 2004 Audi A6, 2002 - 2004 Audi A6 Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A6 Quattro
Quantity2
Installation PositionUpstream Driver & Passenger
Item LocatedUnited States
ConditionNew
item #1001H68A
Show less
Upstream or Downstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Heated | A-Premium APOS2115
A-Premium®Part # APOS2115
Upstream or Downstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Heated | A-Premium APOS2115
4.5667 Reviews
$30.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2021 - 2022 Audi Q7, 2020 - 2024 Audi Q5 PHEV, 2019 - 2020 Audi A6 Quattro, 2019 - 2020 Audi Q5
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A6 Quattro
Installation PositionUpstream or Downstream
Item LocatedUnited States
ConditionNew
item #10188219
Note
【Note-1】 For Audi Q5, This item fits the model from 11/13/2018.
【Note-2】 The shape of the sensing element does not affect its performance.
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Upstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Heated | A-Premium OS060
A-Premium®Part # OS060
Upstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Heated | A-Premium OS060
4.5667 Reviews
$24.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2002 - 2003 Audi S6, 2001 - 2001 Audi Allroad Quattro, 2000 - 2005 Volkswagen Passat, 2000 - 2004 Audi A6 Quattro, 2000 - 2002 Audi S4, 2000 - 2001 Audi A4, 2000 - 2001 Audi A4 Quattro, 2000 - 2001 Audi A6, 2000 - 2001 Audi A6 Quattro, 2000 - 2001 Audi A6 Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A6 Quattro
Quantity1
Installation PositionUpstream
Item LocatedUnited States
ConditionNew
item #100312A7
Show less
Upstream Driver & Passenger O2 Oxygen Sensor | 2-Pc Direct-Fit | Heated | A-Premium APOS1022
A-Premium®Part # APOS1022
Upstream Driver & Passenger O2 Oxygen Sensor | 2-Pc Direct-Fit | Heated | A-Premium APOS1022
4.5667 Reviews
$122.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2017 - 2019 Audi Q7, 2017 - 2018 Audi A7 Quattro, 2017 - 2018 Audi A8 Quattro, 2015 - 2018 Audi A6 Quattro, 2015 - 2017 Audi Q5, 2015 - 2017 Audi S5, 2015 - 2017 Audi SQ5, 2015 - 2016 Audi A7 Quattro, 2015 - 2016 Audi A8 Quattro, 2015 - 2016 Audi S4, 2014 - 2014 Audi A7 Quattro, 2014 - 2014 Audi SQ5, 2013 - 2014 Audi Q5, 2012 - 2013 Audi A7 Quattro, 2010 - 2013 Audi S4, 2010 - 2013 Audi S5, 2009 - 2014 Audi A6 Quattro, 2009 - 2012 Audi Q5, 2008 - 2010 Audi A5 Quattro, 2006 - 2011 Audi A6
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A6 Quattro
Installation PositionUpstream Driver & Passenger
Item LocatedUnited States
ConditionNew
item #1001H438
Note
Oxygen Sensor - B1S1 Indicates Bank 1 Sensor 1, B2S1 Indicates Bank 2 Sensor 1.
【Note-1】For Audi 2014-2016 A7 Quattro & 2015-2016 A8 Quattro, it fits GAS, not DIESEL.
【Note-2】For Audi 2013-2014 Q5 & 2017-2019 Q7, it fits GAS, not DIESEL.
Show less
Downstream Passenger O2 Oxygen Sensor | 1-Pc Direct-Fit | Heated | A-Premium APOS0378
A-Premium®Part # APOS0378
Downstream Passenger O2 Oxygen Sensor | 1-Pc Direct-Fit | Heated | A-Premium APOS0378
4.5667 Reviews
$23.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2009 - 2011 Audi A6 Quattro, 2006 - 2011 Audi A6, 2006 - 2008 Audi A4, 2005 - 2009 Audi A4 Quattro, 2005 - 2008 Audi A6 Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A6 Quattro
Quantity1
Installation PositionDownstream Passenger
Item LocatedUnited States
ConditionNew
item #10031GEY
Show less
Upstream & Downstream O2 Oxygen Sensor | 2-Pc Direct-Fit | Heated | A-Premium OS218
A-Premium®Part # OS218
Upstream & Downstream O2 Oxygen Sensor | 2-Pc Direct-Fit | Heated | A-Premium OS218
4.5667 Reviews
$67.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2002 - 2003 Audi S6, 2001 - 2001 Audi Allroad Quattro, 2000 - 2005 Volkswagen Passat, 2000 - 2004 Audi A6 Quattro, 2000 - 2002 Audi S4, 2000 - 2001 Audi A4, 2000 - 2001 Audi A4 Quattro, 2000 - 2001 Audi A6, 2000 - 2001 Audi A6 Quattro, 2000 - 2001 Audi A6 Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A6 Quattro
Quantity2
Installation PositionUpstream & Downstream
Item LocatedUnited States
ConditionNew
item #1003129D
Show less
Upstream & Downstream O2 Oxygen Sensor | 2-Pc Direct-Fit | Heated | A-Premium APOS1330
A-Premium®Part # APOS1330
Upstream & Downstream O2 Oxygen Sensor | 2-Pc Direct-Fit | Heated | A-Premium APOS1330
4.5667 Reviews
$79.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2017 - 2019 Audi Q7, 2016 - 2018 Audi A6 Quattro, 2016 - 2018 Audi A7 Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Audi A6 Quattro
Quantity2
Installation PositionUpstream & Downstream
Item LocatedUnited States
ConditionNew
item #1001GUHD
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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.

Popular Years for Audi A6 Quattro

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Oct 14, 2026

Why Is My Car Running Worse After a New O2 Sensor?

Car running worse after O2 sensor replacement? Check part compatibility, wiring, and exhaust leaks before assuming a bad sensor. Learn to diagnose fuel trims, verify installation, and avoid costly mistakes with this step-by-step guide.

Oct 13, 2026

Can I Use a Downstream Oxygen Sensor for Upstream?

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