Heated Oxygen Sensor 1 bank 2 too lean
P1147 — Heated Oxygen Sensor 1 bank 2 too lean
System: Powertrain | Type: Manufacturer-Specific | Make: Audi
P1147 is a manufacturer-specific powertrain diagnostic trouble code recorded for Audi vehicles. It belongs to the P-prefix family of codes, which covers engine, transmission, emissions, or fuel-system faults.
When P1147 is stored, the module has detected a bank-specific fault, meaning it applies only to one cylinder bank of a multi-bank engine; and a sensor-related fault — the reported value from the named sensor is out of spec.
Scanning & clearing: A generic OBD-II scan tool will usually read and clear powertrain (P) codes. For live data, freeze-frame capture, and bi-directional tests you may need a more capable scan tool that supports the vehicle's ECM protocol.
P1147 is a manufacturer-specific code. The same code string on a different make may have a different meaning. Always confirm the code's definition against the vehicle's service information for the specific make and model under test.
The upstream heated oxygen sensor on Bank 2, designated Sensor 1, measures the oxygen content of the exhaust ahead of the catalytic converter and feeds the Engine Control Module (ECM) closed loop fuel control. DTC P1147 is set when this sensor reports a persistently lean exhaust on Bank 2 and the ECM reaches the limit of its ability to add fuel in response. The lean indication can be genuine, caused by unmetered air or a fuel shortfall, or false, caused by an exhaust leak drawing air across the sensor or by an aged sensor reading lean. When this code is stored the driver may notice hesitation,...
Detailed possible causes for P1147 are available to TaT members.
Unlock with Free TrialStep-by-step diagnostic guidance for P1147 is available to TaT members. Our Diagnostic Assistant provides professional-level troubleshooting procedures written by experienced technicians.
Unlock with Free Trial| Code | P1147 |
| System | Powertrain |
| Type | Manufacturer-Specific |
| Make | Audi |
| Causes | Available |
| Diag. Assistant | Available |
| Video | — |
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