Fitment

Confirmed OE application based on OEM catalog cross-reference data:

• Audi Q7 (4M platform) 3.0 TDI / 4.0 TDI diesel variants
• Audi SQ7 / SQ8 diesel applications (platform-dependent)
• Volkswagen Touareg (CR / MLBevo platform diesel variants)
• SCR (AdBlue) diesel emission systems

Fitment is strictly based on OE number matching: 4M0907807T

OE catalog data confirms this part belongs to the 4M-series NOx sensor family used on MQB / MLB Evo large SUV diesel platforms.

Technical Description

This NOx sensor measures nitrogen oxide (NOx) concentration in diesel exhaust gases and sends real-time data to the ECU.

It is part of the SCR (Selective Catalytic Reduction) system and is used to control AdBlue dosing strategy, ensuring emission compliance in modern diesel engines.

The sensor is an electronic exhaust-mounted module designed for high-temperature operation and continuous emissions monitoring.

Symptoms / Fault Codes

Common symptoms of failure include:

• Check engine light
• P2200 / P229F fault codes (system dependent)
• SCR / AdBlue system warning
• Reduced engine performance (limp mode)
• Increased emissions

OE / Part Numbers

• 4M0907807T

FAQ

What does this NOx sensor do?

It measures nitrogen oxide levels in diesel exhaust and sends data to the ECU for SCR emission control.

Is this sensor vehicle-specific?

Yes. Compatibility is strictly determined by OE number matching. Even small suffix changes (T / K / AK variants) can indicate different calibration or mounting positions.

Which vehicles use this part?

It is commonly used on Audi Q7/SQ7/SQ8 and Volkswagen Touareg diesel platforms depending on engine and emission configuration.

Can similar NOx sensors be interchangeable?

Not recommended. NOx sensors are ECU-calibrated components and must match exact OE specifications.