LEFT Lambda Oxygen Sensor, BEFORE Catalyst, Cyl 4-6. Porsche 955 Cayenne 3.2L V6 2004-06  ❭  958906262C

Restore accurate air-fuel mixture monitoring and dependable engine-management operation with this OE Match LEFT Lambda Oxygen Sensor. Designed for compatible Porsche applications, this sensor is specified for the LEFT side, cylinders 4–6, and is positioned BEFORE the catalytic converter.

• Porsche 955 Cayenne 3.2L V6 2004-06  

Also known as an oxygen sensor, O2 sensor or lambda probe, this component measures the oxygen content of the exhaust gases leaving the engine. As a pre-catalyst sensor, its readings provide the engine control unit (ECU) with important information about the combustion mixture before the exhaust gases enter the catalytic converter.

The ECU uses this information to determine whether the engine is operating richer or leaner than intended and can make appropriate adjustments to fuel delivery. Accurate lambda feedback helps maintain efficient combustion, smooth engine performance, controlled emissions and correct catalytic converter operation.

Located directly in the hot exhaust stream, lambda sensors endure high temperatures, vibration, thermal cycling and combustion deposits. With age, the sensing element can become contaminated or slow to respond, while the internal heater, wiring or electrical connections may also deteriorate.

This OE Match LEFT Lambda Oxygen Sensor provides a high-quality replacement for a slow, inaccurate, contaminated or failed sensor on the cylinders 4–6 bank.

What This Product Does:

• Measures oxygen content in the exhaust gases.
• Fits the LEFT-side exhaust bank where specified.
• Serves cylinders 4–6.
• Is positioned BEFORE the catalytic converter.
• Sends exhaust-mixture information to the ECU.
• Helps determine whether combustion is rich or lean.
• Supports closed-loop fuel control.
• Allows the ECU to make appropriate fuel corrections.
• Helps maintain the intended air-fuel mixture.
• Supports smooth idle and consistent engine performance.
• Helps maintain responsive acceleration.
• Contributes to efficient fuel consumption.
• Helps control exhaust emissions.
• Supports efficient catalytic converter operation.
• Replaces a faulty or slow-response pre-catalyst sensor.
• Provides an OE Match replacement for compatible Porsche applications.

• Check engine or engine-management warning light.
• Lambda or oxygen sensor fault codes.
• Bank-specific oxygen sensor faults for cylinders 4–6.
• Rich or lean mixture fault codes.
• Sensor heater circuit faults.
• Increased fuel consumption.
• Rough or unstable idle.
• Engine hesitation.
• Poor throttle response.
• Reduced engine performance.
• Uneven engine operation.
• Engine misfires.
• Difficult starting.
• Increased exhaust emissions.
• Failed emissions test.
• Strong fuel smell from the exhaust.
• Slow lambda sensor response during diagnostics.
• Implausible oxygen sensor readings.
• Intermittent sensor signal.
• Heat-damaged sensor wiring.
• Damaged or corroded electrical connector.  

• The before-catalyst lambda sensor is an important part of the engine's fuel-management system.
• When operating in closed-loop control, the ECU uses lambda sensor information to continually refine fuel delivery. If the sensor reports inaccurate information or responds too slowly, the ECU may make inappropriate fuel corrections.
• A lambda sensor does not necessarily stop working completely when worn. It may instead become progressively slower or less accurate, which can make deterioration harder to identify without diagnostic testing.
• Replacing a confirmed faulty OE Match Lambda Oxygen Sensor helps restore accurate mixture feedback for the cylinders 4–6 bank and allows the engine-management system to control fuelling correctly.