Bosch 13540 Oxygen Sensor

Bosch Wideband Oxygen Sensor for Toyota and Lexus

Bosch Validated Oxygen Sensor 13540 is a wideband air-fuel ratio sensor built for precise upstream mixture monitoring. It is a direct-fit, heated replacement with a 4-wire blade terminal design, rectangle connector, and included wiring harness for select Toyota and Lexus applications.

For drivers searching for a Bosch 13540 oxygen sensor for Toyota Avalon, Camry, RAV4, Sienna, Solara, or Lexus ES300, this sensor provides the detailed signal the ECU needs for accurate fuel control across the full lambda range.

Key Features

• Wideband A/F oxygen sensor for continuous air-fuel ratio measurement
• Heated design for faster sensor operation and stable readings
• Specific-fit replacement with threaded mounting
• 4-wire configuration with male blade terminals
• Rectangle connector with included wiring harness
• Metal housing with steel finish for OE-style durability
• 18 mm thread diameter and 22 mm hex size
• Bosch Validated Oxygen Sensor line for OE-proven application coverage

Product Details

Bosch 13540 is part of the Bosch Validated Oxygen Sensor line, a product line focused on direct replacement coverage for specific vehicle applications. Bosch pioneered the wideband A/F oxygen sensor design used in modern engine management, and this unit follows that OE-developed approach with a planar pump-cell style sensor architecture, fast light-off characteristics, and optimized heater control. It is engineered for upstream placement where the ECU relies on precise feedback to manage fuel delivery, drivability, and emissions control.

This part cross-references 8946733030 and 8946741030 for the same application. It is a direct replacement for select Toyota and Lexus models, including Toyota Avalon, Camry, RAV4, Sienna, and Solara, plus Lexus ES300 applications listed below. Bosch 13540 is a strong search match for buyers looking for a wideband upstream oxygen sensor for Toyota Avalon upstream left or right, Toyota Sienna upstream front or rear, and Lexus ES300 upstream left or right.

What It Helps Address

• Incorrect air-fuel ratio readings from a worn upstream sensor
• Check engine light concerns related to oxygen sensor performance
• Rough idle or inconsistent fuel control caused by slow sensor response
• Reduced fuel economy from inaccurate ECU feedback
• Emissions test failures tied to faulty wideband sensor output

Installation Notes

Verify the connector shape, wire count, thread size, and sensor position before installation. This Bosch 13540 oxygen sensor is a threaded, specific-fit unit for upstream locations only, so match the vehicle year, engine configuration, and bank/position listed in the fitment data. Use the existing mounting point and confirm the harness routing allows proper clearance from heat sources and moving components.

• Fits 2000-2004 Toyota Avalon, Upstream Left
• Fits 2000-2004 Toyota Avalon, Upstream Right
• Fits 2001-2003 Toyota RAV4, Upstream Right
• Fits 2001-2003 Toyota Sienna, Upstream Rear
• Fits 2001-2003 Toyota Sienna, Upstream Front
• Fits 2001-2003 Toyota Solara, Upstream Right
• Fits 2001-2003 Toyota Solara, Upstream Left
• Fits 2000-2001 Lexus ES300, Upstream Left
• Fits 2000-2001 Lexus ES300, Upstream Right
• Fits 2001 Toyota Camry, Upstream
• Fits 2001 Toyota Camry, Upstream Right
• Fits 2001 Toyota Camry, Upstream Left

Quality Assurance

Bosch backs this oxygen sensor with more than five decades of OE development in engine management and emissions technology. The Bosch Validated Oxygen Sensor 13540 is built to OE-style standards for accurate signal response, reliable heater performance, and long-term service in demanding thermal conditions.