NGK NTK 5707 OZA660-EE14 Lambda/O2 Oxygen Sensor for BMW 5 Series E34 520i 525i 1989-1997 - Direct Fit Upstream Downstream Front Rear Pre-Cat Post-Cat AFR (B1S1/B1S2) OEM Replacement

NGK 5707 NTK OZA660-EE14 Exhaust Oxygen Probe for BMW E34 520i 525i 1989 to 1997

Restore crisp fueling and clean emissions with this OE-spec exhaust gas sensor from NGK NTK. Engine management relies on accurate feedback to keep the air to fuel mixture in the sweet spot. Swapping a tired probe for this premium replacement can bring back smooth idle, sharper throttle response, improved MPG and help clear emissions-related warning lights on the BMW 5 Series E34 520i and 525i.

Why this sensor is a smart upgrade

• Direct-fit plug and play probe with the correct connector for listed BMW applications
• Precise AFR feedback for stable closed-loop control and consistent drivability
• Engineered for heat, vibration and contamination resilience for long service life
• Ideal when dealing with rough running, poor fuel economy, MOT emissions issues or fault codes
• Trusted brand quality that enthusiasts and technicians rely on

We fit and use these sensors at MJ Modifications and our customers have been consistently pleased with the results. If your E34 feels a bit off, drinks more fuel than it should or flags mixture faults, this high-quality replacement is a proven solution.

Vehicle applications

Position can vary by model year and exhaust configuration. Some cars use a probe before the catalytic converter and another after. Please confirm whether you require the front pre cat sensor or the rear post cat sensor before ordering.

Fitment check before dispatch

For complete peace of mind, we will confirm compatibility prior to shipping. Add your UK registration number or the last 7 digits of your VIN at checkout so we can verify the correct part for your car.

Professional installation

Prefer it supplied and fitted by specialists? MJ Modifications in Warwickshire can install this part for you. Request a fitting quote at info@mjmodifications.co.uk.

Part numbers

• NGK: 5707
• NTK: OZA660-EE14

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