Mercedes-Benz W204/W207/S211 NOx Sensor A0111531728 Original Standard

When your Mercedes-Benz W204, W207, or S211 shows check engine light, abnormal fuel consumption, weak acceleration, or emissions test failure, NOx sensor aging/failure is likely. This sensor monitors NOx in exhaust in real time and feeds ECU to adjust AFR, ensuring emissions compliance and power. OEM A0111531728; suitable for W204 (C-Class), W207 (E-Coupe), S211 (E-State). Installation: cool engine; use special socket to avoid thread damage; apply light anti-seize on threads and tighten to spec.