FITMENT:
Compatible with BMW 1 Series and 3 Series diesel/gasoline N43 engine platforms, including:

• E81 / E82 / E87 / E88
• E90 / E91 / E92 / E93

OEM reference numbers:
11787587130, 5WK96621K (also cross references: 7587130, 7587127, 7582326 series).

This NOx sensor is used in the engine emission monitoring system to measure nitrogen oxide levels in exhaust gas and optimize fuel-air mixture and emissions control (Euro 4/Euro 5-era BMW N43 engines).

Installed in exhaust system (sensor probe mounted before/within emission control section depending on configuration).

KEY DETAILS:

• Sensor type: NOx (Nitrogen Oxide) probe
• System: Emissions / ECU feedback control
• Voltage: typically 12V on N43 platform variants
• Function: monitors NOx levels for combustion and emissions adjustment
• Application: BMW N43 engine family vehicles

FAQ:

Q1: How do I confirm fitment?
A1: Match OEM number 11787587130 or 5WK96621K exactly with your original sensor. BMW N43 engines are very sensitive to part matching.

Q2: Where is it installed?
A2: Mounted on the exhaust system where it measures NOx levels before/after catalytic treatment depending on configuration.

Q3: What happens if it fails?
A3: Engine warning light, rough idle, increased fuel consumption, and emissions-related fault codes.

Q4: Is programming required after replacement?
A4: Some BMW models require ECU adaptation or fault code reset using diagnostic tools (ISTA).

Q5: Is this interchangeable with other BMW NOx sensors?
A5: No — N43 sensors differ from diesel SCR NOx sensors used on later BMW diesel models.