FITMENT:
Compatible with BMW 1 Series and 3 Series models equipped with N43 petrol engines, including:

• E81 / E87 (116i, 118i, 120i)
• E82 / E88 (120i)
• E90 / E91 / E92 / E93 (316i, 318i, 320i)

OEM / Cross reference numbers:

• 11787587130
• 5WK96621J
• 758713005
• 5WK96621K (interchange variant in some catalogs)

This NOx sensor is used in BMW N43 engine emission systems to monitor nitrogen oxide levels in exhaust gases and help the ECU optimize combustion and emissions control.

FUNCTION:

• Measures NOx levels in exhaust gas stream
• Sends data to ECU for fuel-air mixture control
• Supports catalytic converter efficiency management
• Helps maintain emissions compliance (Euro 4/Euro 5 petrol engines)

INSTALLATION POSITION:

• Exhaust system sensor (position varies depending on N43 layout)
• Typically mounted near catalytic converter section

FAQ:

Q1: Is this diesel SCR NOx sensor?
A1: No. This is a petrol engine N43 NOx sensor, not a diesel AdBlue/SCR type sensor.

Q2: What happens if it fails?
A2: Engine warning light, rough running, higher fuel consumption, and emissions fault codes.

Q3: Is it interchangeable with diesel NOx sensors?
A3: No. Petrol N43 NOx sensors are completely different from diesel SCR NOx sensors.

Q4: Does it need programming after replacement?
A4: Some BMW models require ECU adaptation or fault code reset after installation.

Q5: Are all 5WK96621 versions the same?
A5: No. Variants (J/K/F etc.) differ in calibration and hardware revisions, so OEM matching is important.