FITMENT:
Compatible with BMW 5 Series vehicles equipped with the N53B30A petrol engine and NOx catalytic system, including:

• BMW 5 Series F10 (523i / 528i / 530i)
• BMW 5 Series F11 Touring (523i / 528i / 530i)
• Engine code: N53B30A 3.0L inline 6-cylinder petrol
• Euro 5 emission system with NOx storage catalyst

OEM / Cross reference numbers:

• 11787587130 / 11 78 7 587 130
• 5WK96621K / 5WK9 6621K
• 11787590402 (related NOx sensor/catalyst system variant)
• 7587130 / 758713005 (BMW internal references depending on revision)

FUNCTION:

• Measures nitrogen oxide (NOx) levels in exhaust gas (petrol direct injection system)
• Works with NOx catalytic converter (lean burn system)
• Sends data to ECU for fuel mixture control
• Enables stratified charge operation for fuel efficiency
• Maintains Euro 5 emissions compliance

INSTALLATION POSITION:

• Mounted near NOx catalytic converter (underbody exhaust section)
• Part of catalytic converter / front silencer assembly system
• Works in closed-loop feedback with ECU and NOx storage cat

IMPORTANT NOTE:
BMW N53 NOx systems are different from diesel SCR NOx sensors. Key differences:

• This is for petrol (gasoline) lean-burn engine, not diesel SCR
• Works with NOx storage catalyst instead of AdBlue system
• Sensor and NOx ECU are tightly paired (coding often required)
• Faulty NOx sensor can affect fuel trims, misfires, and stratified charge operation

Common issue symptoms include rough idle, reduced MPG, and loss of lean burn mode.

FAQ:

Q1: What engines does it fit?
A1: BMW N53B30A 3.0L petrol engine used in F10/F11 523i, 528i, 530i.

Q2: Is this diesel SCR NOx sensor?
A2: No — this is a petrol NOx storage catalyst sensor, not AdBlue SCR type.

Q3: What are failure symptoms?
A3: Misfires, rough idle, higher fuel consumption, loss of stratified charge mode, engine light.

Q4: Are 11787587130 and 5WK96621K the same?
A4: Yes, 5WK96621K is the Continental OEM supplier reference for BMW 11787587130.

Q5: Does it require programming?
A5: Yes, BMW NOx sensors usually require adaptation/coding with NOx ECU reset after replacement.