Genuine BMW N54 Bank 2 Front O2 Sensor (Upstream Pre-Cat Lambda Sensor) 1200mm - E82 E88 E90 E91 E92 E93 E89 - Fits 135i, 1M, 335i/xi/is, Z4 35i/35is - OEM Part 11787558087

Restore crisp fueling control and smooth drivability with this OE BMW primary oxygen probe for the N54 twin turbo straight six, Bank 2 before the catalyst, cylinders 4 to 6. Exact 1200 mm loom for correct routing and a factory plug for a direct connection. Part number 11787558087.

If you are experiencing rough idle, hesitation, poor MPG, rich or lean running or an emissions warning, replacing the front regulating lambda on Bank 2 is a proven remedy. We fit this sensor on our own cars and customer builds and feedback has been consistently excellent for reliability and consistency.

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Why this OE BMW sensor

• Restores accurate fuel trim and closed loop control for sharper throttle response
• Helps reduce fuel consumption and supports MOT emissions compliance
• Correct 1.2 m lead with the proper connector for a true plug in fit
• Designed specifically for Bank 2 upstream location on N54, cylinders 4 to 6
• Durable OEM quality for long service life compared with universal alternatives

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Key details

• Application: N54 engine, Bank 2 primary position before catalytic converter
• Cable length: 1200 mm
• Fit type: Direct plug in OE connection
• Manufacturer: BMW
• BMW part number: 11787558087

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Vehicle coverage

E chassis BMW with the N54B30:

• 1 Series E82 and E88
  • 135i and 1M
• 3 Series E90 E91 E92 E93
  • 335i, 335xi xDrive and 335is
• Z4 E89
  • sDrive35i and sDrive35is

Location note: Bank 2 equals the side serving cylinders 4 to 6 in the pre cat position.

Matching primary sensor for the opposite bank is available separately if you wish to refresh both sides together.

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Fitting and support

Professional installation available at MJ Modifications in Warwickshire. Request a quote at info@mjmodifications.co.uk. Many owners choose to replace both primary sensors at the same time for balanced readings.

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Compatibility check

We will verify fitment before dispatch. Please provide your UK registration or the last 7 characters of your VIN at checkout.

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Warranty

Two year manufacturer warranty for UK customers and one year for international customers when a VIN is supplied at checkout on compatible vehicles.

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Search terms to help you find the right part

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