Control Lambda Sensor (Pre-Catalyst / Upper) – 8W0906265AJ

Original wideband lambda sensor (oxygen sensor before the catalytic converter / Bank 1 / Bank 2 control sensor), designed for Audi A7 Sportback (4K / 4K8 generation) and Audi A6 C8 (4K2 / 4K5 / 4KA type) with a turbocharged 3.0 V6 TFSI petrol engine (55 TFSI designation / EA839 family / DLZA, DKMB and related codes), based on the MLBevo modular longitudinal platform.

Original VAG group exhaust emission control and engine management component (manufactured by Bosch / NTK for Audi AG, among others). It is responsible for the precise, continuous measurement of oxygen content in the exhaust gases directly before the exhaust gas treatment system (catalytic converter), transmitting the signal in real time to the engine ECU to perfectly select the fuel-air mixture ratio (lambda). A properly functioning sensor guarantees the full power of the 3.0 TFSI unit, optimal fuel consumption, smooth idling, and no Check Engine errors related to the mixture ratio. It features an original factory thermal sleeve for the wiring harness and a sealed OE connector.

Technical specifications:

• Catalog part number (OE): 8W0906265AJ / 8W0 906 265 AJ (interchangeable with revision numbers 8W0906265, 8W0906265R, 8W0906265S and Bosch / NTK designations used for original equipment)

• System / Category: Exhaust system and engine electrical / Sensors and probes (Lambda Sensor / Oxygen O2 Pre-Cat Sensor)

• Sensor type: Wideband control sensor (pre-catalyst / Pre-Cat / Upstream)

• Dedicated engine: 3.0 V6 TFSI (55 TFSI / EA839 family) and related 2.9 TFSI V6

• Mounting location: Exhaust system – before the catalytic converter (exhaust manifold / turbocharger)

• Installation: Original thermal sleeve protecting the wires from high temperatures from the turbocharger, integrated original multi-pin connector

• Steering side: Left (LHD) and Right (RHD) – universal component

• Condition: Original part, used (100% functional – M18 thread in perfect condition, no seized threads or mechanical damage, measuring element clean, wiring harness intact, no chafing or overheating, connector with all clips intact)

• Manufacturer: Audi AG / VAG / Bosch (Original OEM)

Main application:

• Audi:

  • A7 Sportback (type 4K8) – model years 2018 to 2026 (3.0 V6 TFSI / 55 TFSI engines and S7 2.9 TFSI)

  • A6 / A6 Avant / Allroad (type 4K2 / 4K5 / 4KA - C8) – model years 2018 to 2026 (3.0 V6 TFSI / 55 TFSI engines and S6 2.9 TFSI)

  • A8 / S8 (type 4N - D5) – 3.0 TFSI engines (55 TFSI)

  • Q8 / SQ8 (type 4MN) – 3.0 TFSI engines (55 TFSI)

  • Q7 (type 4M / 4MB Facelift) – 3.0 TFSI engines (55 TFSI)

  • S4 / S5 / RS4 / RS5 (type 8W / B9 and F5) – 2.9 / 3.0 TFSI V6 engines

Fitment guarantee and VIN verification

Every sensor undergoes a heater condition check (heating circuit resistance measured with a multimeter) and an inspection of the thread and connector before shipping.

Fitment / installation tip: The designation 8W0 906 265 AJ indicates a pre-catalyst control sensor with a precisely selected cable length for the 3.0 TFSI engine bay geometry in the MLBevo platform. Using an original OEM sensor eliminates problems typical of universal replacements (e.g., delayed response to mixture ratio changes, adaptation errors, or Check Engine light activation). During installation, we recommend using lambda sensor thread lubricant to prevent seizing. Before purchase, we recommend comparing the full OE number on the old sensor body or verifying fitment using the vehicle's VIN.