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Ford Transit-250 Oxygen Sensors

126 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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Oxygen Sensor - Upstream Left - Bosch 17422Oxygen Sensor - Upstream Left - Bosch 17422
BoschPart # 17422
Oxygen Sensor - Upstream Left - Bosch 17422
46 Reviews
$81.99
Low stock: Only 4 left
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2015-2019 Ford Transit-150, 2015-2019 Ford Transit-250, 2015-2019 Ford Transit-350, 2015-2019 Ford Transit-350 HD
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford Transit-250
Quantity1
Installation PositionUpstream Left
Item LocatedUnited States
Part interchange
17422, CK4Z9F472A
item #1002ECGA
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Denso 234-5038 Oxygen Sensor
DensoPart # 234-5038
Denso 234-5038 Oxygen Sensor
4.29 Reviews
$160.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2016-2016 Ford Police Interceptor Sedan, 2016-2016 Lincoln MKS, 2015-2015 Ford Transit-150, 2015-2015 Ford Transit-250, 2015-2015 Ford Transit-350, 2015-2015 Ford Transit-350 HD, 2015-2015 Lincoln MKT, 2014-2015 Ford Police Interceptor Utility, 2013-2016 Lincoln MKZ, 2013-2015 Ford Explorer, 2013-2015 Ford Explorer, 2013-2015 Ford Explorer, 2013-2015 Ford Flex, 2013-2015 Ford Flex, 2013-2015 Ford Flex, 2013-2015 Ford Police Interceptor Sedan, 2013-2015 Ford Police Interceptor Sedan, 2013-2015 Ford Taurus, 2013-2015 Ford Taurus, 2013-2015 Ford Taurus
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford Transit-250
Quantity1
Item LocatedUnited States
Part interchange
234-5038, CA38188G1, ZZDL18861, 24397, 24387, BL3Z9F472A, 9E5Z9F472D, BL3Z9G472A, 
...View more
item #1002H791
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Denso 234-5076 Oxygen Sensor
DensoPart # 234-5076
Denso 234-5076 Oxygen Sensor
4.29 Reviews
$79.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2016-2016 Ford F-150, 2016-2016 Ford F-150, 2015-2019 Ford Transit-150, 2015-2019 Ford Transit-250, 2015-2019 Ford Transit-350, 2015-2019 Ford Transit-350 HD, 2015-2016 Ford F-150, 2015-2016 Ford F-150, 2015-2016 Ford F-150, 2015-2016 Ford F-150, 2015-2016 Ford F-150, 2014-2017 Ford Fiesta, 2012-2020 Lincoln Navigator, 2012-2017 Ford Expedition, 2011-2014 Ford F-150, 2011-2014 Ford F-150, 2011-2014 Ford F-150, 2011-2011 Ford Expedition, 2011-2011 Lincoln Navigator, 2010-2010 Ford F-150
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford Transit-250
Quantity1
Item LocatedUnited States
Part interchange
234-5076, 24326, CK4Z9F472A, 8F9Z9F472E, 8F9Z9F472G, DM5Z9F472A, 17280, 17323, 
...View more
item #1002H8EZ
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Bosch 15383 Oxygen Sensor
BoschPart # 15383
Bosch 15383 Oxygen Sensor
46 Reviews
$66.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2017-2019 Ford Mustang, 2016-2019 Ford Explorer, 2016-2019 Ford Flex, 2016-2019 Ford Police Interceptor Sedan, 2016-2019 Ford Police Interceptor Utility, 2016-2019 Ford Taurus, 2016-2017 Ford Mustang, 2016-2016 Ford Mustang, 2016-2016 Ford Mustang, 2016-2016 Ford Police Interceptor Sedan, 2016-2016 Lincoln MKS, 2016-2016 Lincoln MKZ, 2015-2017 Ford F-150, 2015-2017 Ford F-150, 2015-2017 Ford F-150, 2015-2017 Ford F-150, 2015-2016 Lincoln MKS, 2015-2015 Ford Mustang, 2015-2015 Ford Mustang, 2015-2015 Ford Police Interceptor Sedan
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford Transit-250
Quantity1
Item LocatedUnited States
Part interchange
15383, CA3918861, CA4118861
item #1002DX4Y
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Walker Products 250-25135 Oxygen Sensor
Walker ProductsPart # 250-25135
Walker Products 250-25135 Oxygen Sensor
56 Reviews
$121.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2023-2023 Ford F-150, 2023-2023 Ford Mustang, 2022-2024 Ford Maverick, 2022-2023 Ford F-150, 2022-2023 Ford Transit Connect, 2022-2023 Ford Transit-150, 2022-2023 Ford Transit-250, 2022-2023 Ford Transit-350, 2022-2023 Ford Transit-350 HD, 2022-2022 Ford Escape, 2022-2022 Ford Mustang, 2021-2023 Lincoln Corsair, 2020-2022 Ford Escape, 2020-2021 Ford Mustang, 2020-2021 Ford Transit-350, 2020-2021 Ford Transit-350, 2020-2021 Ford Transit-350, 2020-2021 Ford Transit-350, 2019-2023 Ford Ranger, 2019-2021 Ford Transit Connect
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford Transit-250
Quantity1
Item LocatedUnited States
Part interchange
250-25135
item #1001PE4E
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Bosch 17321 Oxygen Sensor
BoschPart # 17321
Bosch 17321 Oxygen Sensor
46 Reviews
$100.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2016-2019 Ford Explorer, 2016-2016 Ford F-150, 2016-2016 Ford F-150, 2015-2019 Ford Transit-150, 2015-2019 Ford Transit-250, 2015-2019 Ford Transit-350, 2015-2019 Ford Transit-350 HD, 2015-2016 Ford F-150, 2015-2016 Ford F-150, 2015-2016 Ford F-150, 2015-2016 Ford F-150, 2015-2016 Ford F-150, 2015-2016 Lincoln MKC, 2014-2019 Ford Police Interceptor Utility, 2013-2019 Ford Explorer, 2013-2019 Ford Flex, 2013-2019 Ford Police Interceptor Sedan, 2013-2019 Ford Taurus, 2013-2019 Lincoln MKT, 2013-2016 Ford F-450 Super Duty
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford Transit-250
Quantity1
Item LocatedUnited States
Part interchange
17321
item #1002EEW4
Show less
Oxygen Sensor - Downstream Left - Bosch 18193
BoschPart # 18193
Oxygen Sensor - Downstream Left - Bosch 18193
46 Reviews
$85.99
Low stock: Only 3 left
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2016-2019 Ford Transit-150, 2016-2019 Ford Transit-250, 2016-2019 Ford Transit-350, 2016-2019 Ford Transit-350 HD
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford Transit-250
Quantity1
Installation PositionDownstream Left
Item LocatedUnited States
Part interchange
18193, GK4Z9G444A
item #1002EHG2
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Oxygen Sensor - Denso 234-8039
DensoPart # 234-8039
Oxygen Sensor - Denso 234-8039
4.29 Reviews
$72.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2019-2020 Lincoln MKZ, 2019-2019 Ford Edge, 2019-2019 Ford Escape, 2019-2019 Ford Fusion, 2019-2019 Lincoln MKZ, 2019-2019 Lincoln MKZ, 2019-2019 Lincoln Nautilus, 2018-2018 Ford Edge, 2018-2018 Ford Edge, 2018-2018 Ford Edge, 2018-2018 Ford Escape, 2018-2018 Ford Escape, 2018-2018 Ford Escape, 2017-2020 Ford Fusion, 2017-2020 Ford Fusion, 2017-2020 Ford Fusion, 2017-2020 Ford GT, 2017-2020 Lincoln MKZ, 2017-2019 Lincoln MKC, 2017-2019 Lincoln MKZ
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford Transit-250
Quantity1
Item LocatedUnited States
Part interchange
234-8039, GK4Z9G444D, HS7Z9G444A, FB5Z9G444A, FB5Z9G444C, GK4Z9G444E, 22541, 22542, 
...View more
item #1005HRCP
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Oxygen Sensor - Denso 234-8017
DensoPart # 234-8017
Oxygen Sensor - Denso 234-8017
4.29 Reviews
$58.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2021-2022 Ford Expedition, 2021-2022 Lincoln Navigator, 2020-2022 Ford Mustang, 2019-2019 Ford Expedition, 2018-2020 Ford F-150, 2016-2019 Ford Transit-150, 2016-2019 Ford Transit-250, 2016-2019 Ford Transit-350, 2016-2019 Ford Transit-350 HD
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford Transit-250
Quantity1
Item LocatedUnited States
Part interchange
234-8017, GK4Z9G444H, GK4Z9G444C, 22540, 16187, 350-341045, 250-241199
item #1005HL79
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Walker Products 250-25035 Oxygen Sensor
Walker ProductsPart # 250-25035
Walker Products 250-25035 Oxygen Sensor
56 Reviews
$112.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2018-2018 BMW X5, 2017-2017 Hyundai Veloster, 2016-2017 Hyundai Veloster, 2016-2016 Hyundai Veloster, 2016-2016 Hyundai Veloster, 2016-2016 Kia Rio, 2016-2016 Volkswagen Jetta, 2016-2016 Volkswagen Jetta, 2015-2019 Ford Transit-150, 2015-2019 Ford Transit-250, 2015-2019 Ford Transit-350, 2015-2019 Ford Transit-350 HD, 2015-2017 Hyundai Accent, 2015-2017 Kia Rio, 2015-2016 Audi A3, 2015-2016 Ford Lobo, 2015-2015 Volkswagen Beetle, 2015-2015 Volkswagen Beetle, 2015-2015 Volkswagen Golf, 2015-2015 Volkswagen Golf SportWagen
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford Transit-250
Quantity1
Item LocatedUnited States
Part interchange
250-25035
item #1001P87X
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Bosch 15741 Oxygen Sensor
BoschPart # 15741
Bosch 15741 Oxygen Sensor
46 Reviews
$56.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2023-2023 Cadillac XT5, 2023-2023 Cadillac XT6, 2023-2023 Chevrolet Blazer, 2023-2023 GMC Acadia, 2022-2022 Chevrolet Colorado, 2022-2022 GMC Canyon, 2022-2022 Mazda CX-5, 2022-2022 Mazda CX-5, 2022-2022 Mazda CX-5, 2021-2022 Buick Enclave, 2021-2022 Cadillac XT6, 2021-2021 GMC Canyon, 2021-2021 Mazda 6, 2021-2021 Mazda 6, 2021-2021 Mazda CX-5, 2021-2021 Mazda CX-5, 2020-2023 Chevrolet Traverse, 2020-2022 Cadillac XT5, 2020-2022 GMC Acadia, 2020-2022 Lexus RX350
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford Transit-250
Quantity1
Item LocatedUnited States
Part interchange
15741
item #1002E5KY
Show less
Denso 234-5176 Oxygen Sensor
DensoPart # 234-5176
Denso 234-5176 Oxygen Sensor
4.29 Reviews
$66.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2020-2020 Ford Mustang, 2020-2020 Ford Mustang, 2020-2020 Ford Transit Connect, 2017-2019 Ford E-350 Super Duty, 2017-2018 Ford Transit Connect, 2016-2019 Ford Mustang, 2016-2019 Ford Transit-150, 2016-2019 Ford Transit-250, 2016-2019 Ford Transit-350, 2016-2019 Ford Transit-350 HD, 2016-2017 Ford Mustang, 2016-2016 Ford E-350 Super Duty, 2015-2017 Ford F-150, 2015-2017 Ford F-150, 2015-2017 Ford F-150, 2015-2015 Ford Mustang, 2015-2015 Ford Mustang, 2014-2016 Ford Escape, 2014-2016 Ford Fusion, 2014-2016 Ford Transit Connect
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford Transit-250
Quantity1
Item LocatedUnited States
Part interchange
234-5176, 27018, 27019, 27021, 27023, 27030, 27013, 27031, 
...View more
item #1002HDTX
Show less
Walker Products 250-24989 Oxygen Sensor
Walker ProductsPart # 250-24989
Walker Products 250-24989 Oxygen Sensor
56 Reviews
$78.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2020-2020 Ford Mustang, 2020-2020 Ford Mustang, 2019-2019 Ford Mustang, 2017-2018 Ford Mustang, 2017-2017 Ford F-150, 2017-2017 Ford Mustang, 2016-2016 Ford Mustang, 2016-2016 Ford Mustang, 2016-2016 Ford Mustang, 2016-2016 Ford Police Interceptor Sedan, 2016-2016 Lincoln MKS, 2016-2016 Lincoln MKZ, 2015-2017 Ford F-150, 2015-2017 Ford F-150, 2015-2017 Ford F-150, 2015-2016 Ford F-150, 2015-2016 Ford Mustang, 2015-2015 Ford Mustang, 2015-2015 Ford Transit, 2015-2015 Ford Transit-150
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford Transit-250
Quantity1
Item LocatedUnited States
Part interchange
250-24989
item #1001PD6D
Show less
Oxygen Sensor - Downstream Left - Denso 234-4965
DensoPart # 234-4965
Oxygen Sensor - Downstream Left - Denso 234-4965
4.29 Reviews
$68.99
Low stock: Only 4 left
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2015-2015 Ford Transit-150, 2015-2015 Ford Transit-250, 2015-2015 Ford Transit-350, 2015-2015 Ford Transit-350 HD
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford Transit-250
Quantity1
Installation PositionDownstream Left
Item LocatedUnited States
Part interchange
234-4965, CK4Z9G444B, 22543, 350-341078, 250-241186
item #1005HKT1
Show less
Oxygen Sensor - Denso 234-4489
DensoPart # 234-4489
Oxygen Sensor - Denso 234-4489
4.29 Reviews
$48.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2019-2019 Ford Explorer, 2019-2019 Ford Explorer, 2019-2019 Ford Police Interceptor Sedan, 2019-2019 Ford Police Interceptor Utility, 2019-2019 Ford Taurus, 2016-2018 Ford Explorer, 2016-2018 Ford Explorer, 2016-2018 Ford Police Interceptor Utility, 2016-2018 Ford Taurus, 2016-2016 Lincoln MKS, 2015-2015 Ford Explorer, 2015-2015 Ford Taurus, 2015-2015 Ford Transit-150, 2015-2015 Ford Transit-250, 2015-2015 Ford Transit-350, 2015-2015 Ford Transit-350 HD, 2014-2019 Lincoln MKT, 2014-2015 Ford Police Interceptor Utility, 2014-2014 Ford Explorer, 2013-2019 Ford Flex
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford Transit-250
Quantity1
Item LocatedUnited States
Part interchange
234-4489, CA3918861, CA4118861, BE5Z9G444D, BH6Z9G444A, CK4Z9G444D, 22143, 22134, 
...View more
item #1005HKQX
Show less
Walker Products 350-35133 Oxygen Sensor
Walker ProductsPart # 350-35133
Walker Products 350-35133 Oxygen Sensor
56 Reviews
$105.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2016-2016 Ford Police Interceptor Sedan, 2016-2016 Lincoln MKS, 2015-2015 Ford Explorer, 2015-2015 Ford Explorer, 2015-2015 Ford Explorer, 2015-2015 Ford Flex, 2015-2015 Ford Flex, 2015-2015 Ford Flex, 2015-2015 Ford Transit-150, 2015-2015 Ford Transit-250, 2015-2015 Ford Transit-350, 2015-2015 Ford Transit-350 HD, 2014-2015 Ford Police Interceptor Sedan, 2014-2015 Ford Police Interceptor Sedan, 2014-2015 Ford Police Interceptor Utility, 2014-2015 Lincoln MKT, 2014-2014 Ford Explorer, 2014-2014 Ford Explorer, 2014-2014 Ford Explorer, 2014-2014 Ford Flex
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford Transit-250
Quantity1
Item LocatedUnited States
Part interchange
350-35133
item #1001PGSY
Show less
Walker Products 250-25034 Oxygen Sensor
Walker ProductsPart # 250-25034
Walker Products 250-25034 Oxygen Sensor
56 Reviews
$98.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2023-2023 Kia Stinger, 2022-2022 Genesis G90, 2022-2022 Genesis G90, 2022-2022 Kia Stinger, 2021-2023 Kia Seltos, 2021-2023 Kia Soul, 2021-2023 Kia Telluride, 2021-2021 Honda Civic, 2021-2021 Kia Forte, 2021-2021 Kia Sedona, 2021-2021 Kia Stinger, 2020-2023 Audi R8, 2020-2023 Genesis G70, 2020-2022 Genesis G90, 2020-2020 Genesis G80, 2020-2020 Genesis G80, 2020-2020 Genesis G80, 2020-2020 Hyundai Elantra, 2020-2020 Hyundai Palisade, 2020-2020 Kia K900
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford Transit-250
Quantity1
Item LocatedUnited States
Part interchange
250-25034
item #1001P8LN
Show less
Oxygen Sensor - Downstream Right - Bosch 16745
BoschPart # 16745
Oxygen Sensor - Downstream Right - Bosch 16745
46 Reviews
$70.99
Low stock: Only 4 left
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2015-2015 Ford Transit-150, 2015-2015 Ford Transit-250, 2015-2015 Ford Transit-350, 2015-2015 Ford Transit-350 HD
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford Transit-250
Quantity1
Installation PositionDownstream Right
Item LocatedUnited States
Part interchange
16745
item #1002E8Y2
Show less
Walker Products 350-34361 Oxygen Sensor
Walker ProductsPart # 350-34361
Walker Products 350-34361 Oxygen Sensor
56 Reviews
$46.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2016-2019 Ford Explorer, 2016-2019 Ford Explorer, 2016-2019 Ford Flex, 2016-2019 Ford Police Interceptor Sedan, 2016-2019 Ford Taurus, 2015-2016 Lincoln MKS, 2015-2015 Ford Transit, 2015-2015 Ford Transit-150, 2015-2015 Ford Transit-250, 2015-2015 Ford Transit-350, 2015-2015 Ford Transit-350 HD, 2014-2019 Ford Police Interceptor Utility, 2014-2019 Lincoln MKT, 2013-2015 Ford Explorer, 2013-2015 Ford Flex, 2013-2015 Ford Police Interceptor Sedan, 2013-2015 Ford Taurus, 2012-2015 Lincoln MKX, 2012-2014 Ford Edge, 2012-2014 Ford Edge
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford Transit-250
Quantity1
Item LocatedUnited States
Part interchange
350-34361
item #1001PNC5
Show less
Walker Products 350-341014 Oxygen Sensor
Walker ProductsPart # 350-341014
Walker Products 350-341014 Oxygen Sensor
56 Reviews
$40.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2020-2020 Ford F-250 Super Duty, 2020-2020 Lincoln Continental, 2019-2020 Ford F-350 Super Duty, 2019-2019 Ford F-250 Super Duty, 2019-2019 Ford Flex, 2019-2019 Ford Flex, 2019-2019 Ford Flex, 2019-2019 Ford Police Interceptor Sedan, 2019-2019 Ford Police Interceptor Sedan, 2019-2019 Ford Taurus, 2019-2019 Ford Taurus, 2019-2019 Ford Taurus, 2019-2019 Lincoln Continental, 2019-2019 Lincoln Continental, 2019-2019 Lincoln MKT, 2018-2020 Lincoln MKZ, 2018-2019 Ford E-350 Super Duty, 2018-2019 Ford Police Interceptor Utility, 2018-2019 Ford Transit-350, 2018-2019 Lincoln Continental
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford Transit-250
Quantity1
Item LocatedUnited States
Part interchange
350-341014
item #1001PAX3
Show less
Page 4 of 7

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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