24/7 Customer service
To make aftermarket auto parts an afterthought.
Add your vehicle
Address
Login
Cart
Item
$0.00
Add your vehicle to ensure fitment/Choose a yearRequired Fields
Select a different vehicle
Make/Model
VIN
Save

Ram Oxygen Sensors

187 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.

  • All filters
  • Sort By
  • Year
  • Model
  • Price
  • Placement on Vehicle
  • Brand
  • Color
  • Warranty
2011-2018 2021-2024 Ram 2500 Upstream or Downstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Aisin OXSAZ-003172011-2018 2021-2024 Ram 2500 Upstream or Downstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Aisin OXSAZ-00317
AisinPart # OXSAZ-00317
2011-2018 2021-2024 Ram 2500 Upstream or Downstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Aisin OXSAZ-00317
4.5683 Reviews
$43.99
Low stock: Only 4 left
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits Ram 2500: 2011 2012 2013 2014 2015 2016 2017 2018 2021 2022 2023 2024
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ram
Quantity1
Installation PositionUpstream or Downstream
Item LocatedUnited States
ConditionNew
item #1018GEAC
Show less
2015-2017 Ram ProMaster 1500 Upstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Aisin OXSAZ-00577
AisinPart # OXSAZ-00577
2015-2017 Ram ProMaster 1500 Upstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Aisin OXSAZ-00577
4.5683 Reviews
$97.99
Low stock: Only 3 left
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits Ram ProMaster 1500: 2015 2016 2017
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ram
Quantity1
Installation PositionUpstream
Item LocatedUnited States
ConditionNew
item #1018G2YK
Show less
2015-2017 Ram ProMaster 2500 Upstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Aisin OXSAZ-00577
AisinPart # OXSAZ-00577
2015-2017 Ram ProMaster 2500 Upstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Aisin OXSAZ-00577
4.5683 Reviews
$97.99
Low stock: Only 3 left
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits Ram ProMaster 2500: 2015 2016 2017
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ram
Quantity1
Installation PositionUpstream
Item LocatedUnited States
ConditionNew
item #1018G495
Show less
2015-2017 Ram ProMaster 3500 Upstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Aisin OXSAZ-00577
AisinPart # OXSAZ-00577
2015-2017 Ram ProMaster 3500 Upstream O2 Oxygen Sensor | 1-Pc Direct-Fit | Aisin OXSAZ-00577
4.5683 Reviews
$97.99
Low stock: Only 3 left
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits Ram ProMaster 3500: 2015 2016 2017
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ram
Quantity1
Installation PositionUpstream
Item LocatedUnited States
ConditionNew
item #1018G2L3
Show less
Bosch 15510 Oxygen Sensor
BoschPart # 15510
Bosch 15510 Oxygen Sensor
46 Reviews
$62.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2022-2022 Chrysler 300, 2022-2022 Dodge Challenger, 2022-2022 Dodge Charger, 2022-2022 Dodge Durango, 2022-2022 Dodge Durango, 2022-2022 Jeep Cherokee, 2022-2022 Jeep Grand Cherokee WK, 2022-2022 Mercedes-Benz SL63 AMG, 2021-2022 Dodge Durango, 2021-2021 Chrysler 300, 2021-2021 Dodge Charger, 2021-2021 Dodge Durango, 2021-2021 Dodge Durango, 2020-2022 Chrysler Pacifica, 2020-2022 Chrysler Voyager, 2020-2022 Dodge Challenger, 2020-2022 Dodge Charger, 2020-2022 Dodge Durango, 2020-2022 Ram 1500 Classic, 2020-2021 Dodge Challenger
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ram
Quantity1
Item LocatedUnited States
Part interchange
15510, 5149171AA, 5149171AB, 5149180AA, 5149180AB, 56029049AA, 5033500AA, 56028994AB, 
...View more
item #1002DVN9
Show less
Bosch 17212 Oxygen Sensor
BoschPart # 17212
Bosch 17212 Oxygen Sensor
46 Reviews
$100.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2012-2012 Ram 2500, 2012-2012 Ram 3500, 2011-2012 Ram 4500, 2011-2012 Ram 5500, 2011-2011 Ram 2500, 2011-2011 Ram 3500, 2010-2010 Dodge Ram 2500, 2010-2010 Dodge Ram 3500, 2008-2010 Dodge Ram 4500, 2008-2010 Dodge Ram 5500, 2008-2009 Dodge Ram 2500, 2007-2009 Dodge Ram 3500, 2007-2007 Dodge Ram 2500
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ram
Quantity1
Item LocatedUnited States
Part interchange
17212, 5149263AA, 68067170AA, 68328896AA
item #1002EC86
Show less
Oxygen Sensor - Upstream - Bosch 17009
BoschPart # 17009
Oxygen Sensor - Upstream - Bosch 17009
46 Reviews
$87.99
Low stock: Only 4 left
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2014-2019 Jeep Grand Cherokee, 2014-2017 Ram ProMaster 1500, 2014-2017 Ram ProMaster 2500, 2014-2017 Ram ProMaster 3500, 2014-2015 Chevrolet Cruze
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ram
Quantity1
Installation PositionUpstream
Item LocatedUnited States
Part interchange
17009, 68146231AB, 12644786, 68146231AC
item #1002E8RG
Show less
Oxygen Sensor - Upstream - Bosch 16562
BoschPart # 16562
Oxygen Sensor - Upstream - Bosch 16562
46 Reviews
$199.99
Low stock: Only 2 left
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2018-2020 Jeep Compass, 2017-2017 Jeep Compass, 2016-2018 Fiat 500X, 2015-2020 Jeep Renegade, 2015-2020 Ram ProMaster City, 2015-2017 Chrysler 200, 2014-2020 Jeep Cherokee
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ram
Quantity1
Installation PositionUpstream
Item LocatedUnited States
Part interchange
16562, 68195741AA
item #1002E814
Show less
Bosch 15511 Oxygen Sensor
BoschPart # 15511
Bosch 15511 Oxygen Sensor
46 Reviews
$47.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2011-2011 Ram 2500, 2011-2011 Ram 3500, 2009-2010 Volkswagen Routan, 2004-2005 Dodge Ram 1500, 2004-2004 Jeep Grand Cherokee, 2004-2004 Jeep TJ, 2004-2004 Jeep Wrangler, 2003-2006 Dodge Viper, 2003-2003 Dodge Ram 3500, 2001-2003 Dodge Dakota, 2001-2003 Dodge Dakota, 2001-2003 Dodge Dakota, 2001-2003 Dodge Dakota, 2001-2003 Dodge Dakota, 2001-2003 Dodge Dakota, 2001-2003 Dodge Durango
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ram
Quantity1
Item LocatedUnited States
Part interchange
15511, 5149283AA, 56028995AA, 56041699AA, 7B0906265
item #1002DYW2
Show less
Oxygen Sensor - Bosch 18086
BoschPart # 18086
Oxygen Sensor - Bosch 18086
46 Reviews
$200.99
Low stock: Only 2 left
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2015-2015 Mercedes-Benz C250, 2014-2020 Ram 4500, 2014-2020 Ram 5500, 2013-2014 Mercedes-Benz C250, 2012-2015 Mercedes-Benz SLK250, 2012-2012 Mercedes-Benz C250
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ram
Quantity1
Item LocatedUnited States
Part interchange
18086, 68234701AA, 0065422218
item #1002EA8U
Show less
Oxygen Sensor - Bosch 18126
BoschPart # 18126
Oxygen Sensor - Bosch 18126
46 Reviews
$53.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2021-2022 Ram 2500, 2021-2022 Ram 3500, 2019-2022 Ram 1500 Classic, 2016-2018 Ram 1500, 2015-2017 Dodge Viper, 2014-2018 Ram 2500, 2014-2018 Ram 3500, 2013-2016 Dodge Dart, 2013-2014 SRT Viper, 2011-2018 Ram 2500, 2011-2018 Ram 3500, 2011-2015 Ram 1500, 2011-2011 Ram 1500, 2011-2011 Ram Dakota, 2010-2010 Chrysler PT Cruiser, 2009-2010 Dodge Dakota, 2009-2010 Dodge Ram 1500, 2009-2009 Chrysler Aspen, 2009-2009 Chrysler PT Cruiser, 2009-2009 Dodge Durango
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ram
Quantity1
Item LocatedUnited States
Part interchange
18126, 56029050AA, 68090640AA, 68090640AB
item #1002EHGD
Show less
Oxygen Sensor - Rear Side - Delphi ES10596
DelphiPart # ES10596
Oxygen Sensor - Rear Side - Delphi ES10596
4.647 Reviews
$88.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2023-2023 Dodge Durango, 2023-2023 Ram 1500 Classic, 2022-2022 Dodge Charger, 2022-2022 Jeep Grand Cherokee WK, 2022-2022 Mercedes-Benz SL63 AMG, 2021-2023 Dodge Durango, 2021-2023 Ram 2500, 2021-2022 Ram 1500 Classic, 2021-2021 Dodge Durango, 2021-2021 Jeep Grand Cherokee, 2020-2023 Chrysler Voyager, 2020-2021 Dodge Challenger, 2020-2020 Dodge Durango, 2019-2020 Dodge Charger, 2019-2020 Dodge Charger, 2019-2020 Jeep Grand Cherokee, 2019-2020 Ram 1500 Classic, 2019-2020 Ram 1500 Classic, 2019-2020 Ram 1500 Classic, 2019-2020 Ram 1500 Classic
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ram
Quantity1
Installation PositionRear
Item LocatedUnited States
Part interchange
ES10596, SU3338, SU6893, 250-24253, 234-4411, 234-4547, 234-4559, 234-4587, 
...View more
item #1001X8DT
Show less
Oxygen Sensor - Rear Left Driver Side - Delphi ES11003
DelphiPart # ES11003
Oxygen Sensor - Rear Left Driver Side - Delphi ES11003
4.647 Reviews
$47.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2013-2013 Ram 1500, 2013-2013 Ram 1500, 2013-2013 Ram 1500, 2013-2013 Ram 1500, 2012-2012 Chrysler 300, 2012-2012 Chrysler 300, 2012-2012 Dodge Charger, 2012-2012 Jeep Liberty, 2012-2012 Ram 1500, 2012-2012 Ram 1500, 2011-2012 Dodge Challenger, 2011-2012 Dodge Challenger, 2011-2012 Dodge Charger, 2011-2011 Chrysler 300, 2011-2011 Dodge Nitro, 2011-2011 Jeep Liberty, 2011-2011 Ram 1500, 2011-2011 Ram 1500, 2011-2011 Ram 1500, 2011-2011 Ram 1500
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ram
Quantity1
Installation PositionRear Left
Item LocatedUnited States
Part interchange
ES11003, SU3264, SU6884, 2131372, 2131374, 2131536, 250-24253, 7B0 906 262 A, 
...View more
item #1001X9X2
Show less
Oxygen Sensor - Rear Right Passenger Side - Delphi ES10882
DelphiPart # ES10882
Oxygen Sensor - Rear Right Passenger Side - Delphi ES10882
4.647 Reviews
$51.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2011-2011 Dodge Durango, 2011-2011 Jeep Grand Cherokee, 2011-2011 Ram 1500, 2011-2011 Ram 1500, 2011-2011 Ram 2500, 2011-2011 Ram 3500, 2011-2011 Ram Dakota, 2011-2011 Ram Dakota, 2011-2011 Ram Dakota, 2010-2011 Jeep Wrangler, 2010-2010 Chrysler PT Cruiser, 2010-2010 Chrysler Town & Country, 2010-2010 Dodge Dakota, 2010-2010 Dodge Ram 1500, 2009-2010 Volkswagen Routan, 2009-2009 Chrysler Aspen, 2009-2009 Chrysler PT Cruiser, 2009-2009 Chrysler Town & Country, 2009-2009 Dodge Dakota, 2009-2009 Dodge Durango
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ram
Quantity1
Installation PositionRear Right
Item LocatedUnited States
Part interchange
ES10882, SU3265, SU6887, 2131536, 250-24460, 7B0 906 265, 234-4029, 234-4410, 
...View more
item #1001XCDR
Show less
Denso 234-4545 Oxygen Sensor
DensoPart # 234-4545
Denso 234-4545 Oxygen Sensor
4.29 Reviews
$51.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2023-2024 Dodge Durango, 2023-2023 Chrysler 300, 2023-2023 Chrysler 300, 2023-2023 Dodge Challenger, 2023-2023 Dodge Challenger, 2023-2023 Ram 1500 Classic, 2023-2023 Ram 1500 Classic, 2023-2023 Ram 1500 Classic, 2023-2023 Ram 1500 Classic, 2022-2024 Chrysler Grand Caravan, 2022-2024 Dodge Durango, 2022-2023 Dodge Charger, 2022-2022 Chrysler 300, 2022-2022 Dodge Challenger, 2022-2022 Dodge Challenger, 2022-2022 Jeep Grand Cherokee WK, 2022-2022 Ram 1500 Classic, 2021-2024 Dodge Durango, 2021-2024 Ram 3500, 2021-2023 Dodge Charger
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ram
Quantity1
Item LocatedUnited States
Part interchange
234-4545, 23162, 5149180AA, 7B0906262B, ES10917, 250-24680, 350-34213
item #1005HLC7
Show less
Oxygen Sensor - Denso 234-4547
DensoPart # 234-4547
Oxygen Sensor - Denso 234-4547
4.29 Reviews
$48.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2023-2023 Chrysler 300, 2023-2023 Chrysler Pacifica, 2023-2023 Dodge Charger, 2023-2023 Dodge Charger, 2023-2023 Dodge Charger, 2023-2023 Dodge Durango, 2023-2023 Dodge Durango, 2023-2023 Dodge Durango, 2023-2023 Dodge Durango, 2023-2023 Ram 2500, 2022-2023 Chrysler 300, 2022-2023 Chrysler Grand Caravan, 2022-2023 Ram 1500 Classic, 2022-2023 Ram 1500 Classic, 2022-2022 Dodge Durango, 2022-2022 Jeep Grand Cherokee WK, 2022-2022 Jeep Grand Cherokee WK, 2022-2022 Jeep Grand Cherokee WK, 2022-2022 Jeep Grand Cherokee WK, 2022-2022 Jeep Grand Cherokee WK
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ram
Quantity1
Item LocatedUnited States
Part interchange
234-4547, 23161, 68144248AA, 5149171AA, 5149171AB, ES10596, 250-24680, 250-24253, 
...View more
item #1005HQEV
Show less
Denso 234-4588 Oxygen Sensor
DensoPart # 234-4588
Denso 234-4588 Oxygen Sensor
4.29 Reviews
$42.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2011-2012 Ram 1500, 2011-2011 Ram 1500, 2011-2011 Ram 2500, 2011-2011 Ram 3500, 2011-2011 Ram Dakota, 2010-2010 Chrysler PT Cruiser, 2010-2010 Dodge Challenger, 2010-2010 Dodge Ram 1500, 2009-2010 Chrysler 300, 2009-2010 Dodge Dakota, 2009-2010 Volkswagen Routan, 2009-2009 Chrysler Aspen, 2009-2009 Chrysler PT Cruiser, 2009-2009 Dodge Challenger, 2009-2009 Dodge Charger, 2009-2009 Dodge Durango, 2009-2009 Dodge Ram 1500, 2009-2009 Mitsubishi Raider, 2008-2010 Chrysler Town & Country, 2008-2010 Chrysler Town & Country
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ram
Quantity1
Item LocatedUnited States
Part interchange
234-4588, 23137, 23158, 56028995AA, 56029050AA, OS2221, OS2227, 7B0906265, 
...View more
item #1005HLES
Show less
Denso 234-4274 Oxygen Sensor
DensoPart # 234-4274
Denso 234-4274 Oxygen Sensor
4.29 Reviews
$57.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2013-2014 Ram 1500, 2012-2013 Ram 1500, 2012-2012 Chrysler 300, 2012-2012 Chrysler 300, 2012-2012 Dodge Challenger, 2012-2012 Dodge Challenger, 2012-2012 Dodge Charger, 2012-2012 Dodge Charger, 2011-2012 Jeep Liberty, 2011-2012 Ram 1500, 2011-2011 Chrysler 300, 2011-2011 Dodge Challenger, 2011-2011 Dodge Nitro, 2011-2011 Dodge Nitro, 2011-2011 Ram 1500, 2011-2011 Ram 1500, 2011-2011 Ram 1500, 2011-2011 Ram 2500, 2011-2011 Ram 3500, 2011-2011 Ram Dakota
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ram
Quantity1
Item LocatedUnited States
Part interchange
234-4274, 23135, 23152, 23159, 56029049AA, 56028992AA, 68078717AB, 56028994AA, 
...View more
item #1004YXWZ
Show less
Denso 234-5150 Oxygen Sensor, Upstream
DensoPart # 234-5150
Denso 234-5150 Oxygen Sensor, Upstream
4.29 Reviews
$104.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2022-2022 Jeep Compass, 2022-2022 Jeep Compass, 2022-2022 Jeep Compass, 2021-2022 Jeep Compass, 2021-2022 Jeep Compass, 2021-2022 Jeep Compass, 2021-2022 Jeep Compass, 2021-2022 Jeep Compass, 2021-2022 Jeep Compass, 2021-2022 Jeep Compass, 2021-2021 Jeep Compass, 2021-2021 Jeep Compass, 2020-2020 Jeep Compass, 2019-2019 Jeep Compass, 2018-2018 Fiat 500X, 2018-2018 Jeep Wrangler JK, 2018-2018 Jeep Wrangler JK, 2018-2018 Jeep Wrangler JK, 2017-2017 Fiat 500X, 2017-2017 Fiat 500X
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ram
Quantity1
Installation PositionUpstream
Item LocatedUnited States
Part interchange
234-5150, 27009, 27003, 68195741AA, 68492338AA, 68087364AA, 250-25128, 350-35162, 
...View more
item #1002H740
Show less
Air / Fuel Ratio Sensor - Denso 234-5170
DensoPart # 234-5170
Air / Fuel Ratio Sensor - Denso 234-5170
4.29 Reviews
$145.99
Low stock: Only 5 left
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2019-2019 Jeep Grand Cherokee, 2019-2019 Ram 1500 Classic, 2016-2018 Jeep Grand Cherokee, 2016-2018 Ram 1500, 2016-2016 Ram ProMaster 1500, 2016-2016 Ram ProMaster 2500, 2016-2016 Ram ProMaster 3500, 2014-2015 Ram 1500, 2014-2014 Ram ProMaster 1500, 2014-2014 Ram ProMaster 2500, 2014-2014 Ram ProMaster 3500
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ram
Quantity1
Item LocatedUnited States
Part interchange
234-5170, 27045, 27084, 68146231AB, 68146231AC, 68171190AA, 17213, 350-35089, 
...View more
item #1002H8GG
Show less
Page 8 of 10

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.

Related Blogs

P0175 Code: System Too Rich (Bank 2) What to Check and Fix

Diagnose P0175 (System Too Rich, Bank 2) by comparing fuel trims. Isolate Bank 2 injector or sensor faults versus shared MAF, pressure, or purge issues. Follow our step-by-step guide to fix it safely and avoid unnecessary part replacements.

Nov 02, 2026

P0139 Code: Bank 1 Sensor 2 Slow Response & Fixes

Fix P0139 (Bank 1 Sensor 2 Slow Response) by checking wiring, exhaust leaks, and heater circuits before replacing the sensor. Learn step-by-step diagnosis, proper part selection, and why this code doesn't always mean a bad catalytic converter.

Oct 28, 2026

Best O2 Sensor Brands: Choose the Right Replacement

Compare top O2 sensor brands like A-Premium, DENSO, NTK, and Bosch. Learn to verify fitment, distinguish upstream/downstream sensors, and avoid common buying mistakes for a reliable, cost-effective replacement.

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