Okay, let's break down those OBD-II trouble codes:
These codes (P0153, P0154) refer to issues specifically with the **Oxygen sensor located ahead of the catalytic converter**, which is part of your vehicle's exhaust system monitoring for emissions control.
Here's a breakdown of each code you mentioned:
### P0153: Oxygen Sensor Circuit Malfunction - Bank 1, Sensor 2 (Aging/Poor Signal) or similar variations
* This refers to an issue detected by the PCM in the circuit for the **Oxygen sensor located ahead of the catalytic converter**.
* It monitors oxygen levels *before* passing through your catalytic converter.
### P0154: Oxygen Sensor Voltage High (Bank 2, Sensor 2) - Bank 2
The codes **P0153**, **7**, and **8** all relate to the upstream (ahead of catalyst) O₂ sensors. Here's what each specific code means:
| Code | Description |
|------|-------------|
| P0154 | Oxygen sensor circuit high input detected for bank 1, sensor 2 (upstream). |
### Key Points
* These are all serious engine performance codes that require attention.
* They relate to O₂ sensors located *before* the catalytic converter.
The user should be aware these are serious codes requiring professional diagnosis and repair. A mechanic is needed for proper testing using specialized tools like an OBD-II scanner or thermal couple tester behind the catalyst circuit wires, especially if there's a possible exhaust leak between bank 1 upstream sensor and the catalyst.
