NOx Sensor 4G0907807M

BG 201349 (OE 4G0907807M): function on the vehicle

NOx Sensor 4G0907807M is supplied by BEST GROWTH under part number 201349, cross-referenced to OE 4G0907807M, as a direct-fit aftermarket nox sensors. In service it supplies the emissions-monitoring value the OBD system uses to decide whether the SCR stage is still working within its legal window. A drifting cell triggers inducement long before the catalyst itself is worn out.

BG 201349 is built to the position defined by its OE application on a 12V electrical system in passenger car service on the platform from Volkswagen. Position, calibration and connector layout are part of the specification, so a part that physically fits is not automatically the correct part.

Because the sensor carries its own control module, most "sensor" faults are really bus, supply or ground faults at the connector — the electrical side is worth ten minutes before the part is ordered.

Fitment for Volkswagen and OE cross reference

BG 201349 replaces 1 OE reference: 4G0907807M. Always confirm the number printed on the removed part, including any supersession issued by the vehicle manufacturer.

Recorded vehicle coverage for 201349 includes Volkswagen, typically on A6 / A6 Allroad 2010-2018. Coverage lists are a starting point for identification, not a substitute for checking the OE number on the vehicle.

Quote the number printed on your part with the engine code when you enquire; a single-reference part is the most common source of ordering errors when a platform received a mid-life update.

Symptoms that lead to replacing 4G0907807M

These complaints bring a vehicle in with the Volkswagen nox sensors under suspicion. None of them prove BG 201349 has failed on its own, which is why the checks below matter before a replacement is ordered.

• torque derate or speed inducement with a full, in-spec DEF tank
• no communication with the sensor control module after a cold start
• sensor value frozen at a fixed number once the exhaust warms up
• dosing shut-down after a few minutes of steady-state running
• upstream and downstream values reading almost identically under load

Checks before fitting BG 201349

Aftertreatment faults are usually system faults. Working through these checks prevents a repeat failure after the new nox sensors is fitted.

• Check for exhaust leaks ahead of the sensor boss; a diluted sample reads low NOx.
• Read the sensor's own dew-point release time — a cell that never heats is a supply or module fault.
• Verify DEF concentration with a refractometer before blaming the measuring cell.
• Check for a pending software or parameter update for the sensor control module on that platform.
• After fitting, run the manufacturer's adaptation or relearn so stored efficiency counters reset.

Quality, packaging and ordering 201349

BG 201349 is manufactured and tested to aftermarket replacement standards, with electrical, leakage and functional testing carried out before packing on the 12V specification. Bulk and retail packaging, private-label cartons and customer-specific labelling are available for distributors and workshop groups.

Send OE 4G0907807M or the number printed on your part, the engine code and the vehicle identification number with your enquiry, and our technical team will confirm the correct reference, current stock position and lead time before you commit to an order.

Frequently asked questions

Does BG 201349 replace OE 4G0907807M?

Yes. BG 201349 is listed against 4G0907807M. Confirm the number printed on the removed part and any manufacturer supersession before ordering.

Which vehicles does BG 201349 fit?

Recorded coverage includes Volkswagen. It is supplied as a direct-fit aftermarket nox sensors on 12V systems. Adaptation, reset or relearn procedures required by the vehicle manufacturer still apply after installation.

Does this fault code always mean the nox sensors has failed?

No. Exhaust leaks, wiring and connector damage, reductant quality, dosing performance and upstream engine faults can all produce the same codes. Validate those inputs before replacing BG 201349.