Why one part has five numbers
A single NOx sensor carries up to four identifiers: the vehicle manufacturer’s OE number (4K0907807G), the sensor maker’s number (Continental A2C…, Bosch 0 281 00…), the aftermarket cross (NGK 5WK9…), and the internal logistics SKU. Dealers price by the first; everybody searches by whichever number is printed on the box they already have.
How to cross-reference correctly
- Read the number on the part — the control head or probe body, not the invoice.
- Match the platform, not the brand badge — a 4K0907807G fits Audi A6/A7 C8 3.0 TDI, not “every VW”.
- Watch the suffix letter — 4K0907807A through -AJ differ in calibration; supersessions exist within families.
- Check the connector — pin count and keyway must match.
Use our fitment checker
Type any OE number into the fitment checker — it maps to the exact listing. Or browse by brand and the full shop. Every listing carries the complete cross-reference list in the description.