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2020 Toyota Highlander Oxygen Sensors

65 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 - Bosch 18172Oxygen Sensor - Bosch 18172
SOLD OUT
BoschPart # 18172
Oxygen Sensor - Bosch 18172
46 Reviews
$167.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2020-2022 Lexus RX350, 2019-2019 Lexus RX350, 2019-2019 Toyota Highlander, 2017-2020 Toyota Sienna, 2017-2018 Toyota Highlander, 2017-2018 Toyota Highlander, 2017-2018 Toyota Highlander, 2017-2018 Toyota Highlander, 2017-2018 Toyota Highlander, 2017-2018 Toyota Highlander, 2017-2018 Toyota Highlander, 2016-2022 Lexus RX450h, 2016-2018 Lexus RX350
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: 2020 Toyota Highlander
Quantity1
Item LocatedUnited States
Part interchange
18172, 894670E240
item #1002ECGQ
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Air / Fuel Ratio Sensor - Upstream - Denso 234-9307SOLD OUT
DensoPart # 234-9307
Air / Fuel Ratio Sensor - Upstream - Denso 234-9307
4.29 Reviews
$179.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2023-2023 Toyota Sienna, 2023-2023 Toyota Sienna, 2023-2023 Toyota Sienna, 2023-2023 Toyota Sienna, 2023-2023 Toyota Sienna, 2023-2023 Toyota Sienna, 2022-2022 Lexus NX250, 2022-2022 Lexus NX450h+, 2022-2022 Toyota Camry, 2022-2022 Toyota Sienna, 2021-2023 Toyota Highlander, 2021-2022 Lexus ES250, 2021-2022 Toyota RAV4 Prime, 2021-2022 Toyota Venza, 2021-2021 Toyota Sienna, 2020-2020 Toyota Highlander, 2019-2022 Lexus ES300h, 2019-2022 Toyota Avalon, 2019-2022 Toyota RAV4, 2018-2021 Toyota Camry
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: 2020 Toyota Highlander
Quantity1
Installation PositionUpstream
Item LocatedUnited States
Part interchange
234-9307, 8946733290, 8946706250, 894670E280
item #1002HH9L
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Air / Fuel Ratio Sensor - Denso 234-9143SOLD OUT
DensoPart # 234-9143
Air / Fuel Ratio Sensor - Denso 234-9143
4.29 Reviews
$217.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2022-2022 Lexus IS350, 2022-2022 Lexus IS500, 2021-2022 Toyota Highlander, 2020-2020 Toyota Highlander, 2018-2022 Lexus IS300, 2018-2022 Lexus LC500, 2018-2022 Lexus RC300, 2018-2021 Lexus NX300, 2016-2022 Toyota 4Runner, 2016-2020 Lexus GS F, 2016-2017 Lexus IS300, 2016-2017 Lexus LS460, 2016-2017 Lexus RC300, 2015-2022 Lexus RC F, 2015-2022 Lexus RC350, 2015-2018 Lexus GS450h, 2015-2017 Lexus NX200t, 2015-2015 Toyota 4Runner, 2014-2021 Lexus IS350, 2014-2020 Lexus GS350
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: 2020 Toyota Highlander
Quantity1
Item LocatedUnited States
Part interchange
234-9143, 8946778010, 8946730080, 8946711050, 8946750080, 8946753070, 8946735120, 894670E270, 
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item #1002HE5W
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Walker Products 250-54128 Oxygen SensorSOLD OUT
Walker ProductsPart # 250-54128
Walker Products 250-54128 Oxygen Sensor
56 Reviews
$196.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2022-2022 Toyota Highlander, 2020-2021 Toyota Highlander
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: 2020 Toyota Highlander
Quantity1
Item LocatedUnited States
Part interchange
250-54128
item #1001PC7Q
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Walker Products 250-241178 Oxygen SensorSOLD OUT
Walker ProductsPart # 250-241178
Walker Products 250-241178 Oxygen Sensor
56 Reviews
$73.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2022-2022 Lexus RX350, 2022-2022 Lexus RX350L, 2022-2022 Lexus RX450h, 2022-2022 Lexus RX450hL, 2018-2021 Lexus RX350L, 2018-2021 Lexus RX450hL, 2017-2019 Toyota Highlander, 2016-2021 Lexus RX350, 2016-2021 Lexus RX450h
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: 2020 Toyota Highlander
Quantity1
Item LocatedUnited States
Part interchange
250-241178
item #1001PDNV
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Page 4 of 4

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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