P0174 Fault Diagnosis for 2002 LS1 Camaro SS - Intermittent Lean Bank 2 Issue
Since purchasing my 2002 LS1 Camaro SS, I've been struggling with a recurring P0174 diagnostic trouble code indicating a lean condition in Bank 2. I have already replaced: - All four oxygen (O2) sensors - Intake manifold gaskets - PCV hoses - Spark plugs and ignition wires Fuel injectors were professionally tested and cleaned, and the MAF sensor is confirmed to be functioning correctly. I've also verified the O2 sensor wiring from the intake manifold to the Powertrain Control Module (PCM). The issue manifests intermittently: at times, the upstream O2 sensor operates normally, but the B2S1 O2 sensor suddenly remains in a high reading state without apparent cause. This triggers STFT values rising to 25% and LTFT values reaching 50%, ultimately setting the P0174 code. When idling, the engine exhibits pulsing behavior similar to a mild camshaft effect—sometimes more pronounced than others. I've ruled out common causes such as vacuum leaks through multiple inspections and replacements. I’ve also swapped and tested fuel injectors between banks with no difference in performance. Despite these efforts, the issue persists. Any insights or troubleshooting steps specific to this 2002 LS1 Camaro SS model would be greatly appreciated! Jon
Have you made any modifications such as K&N filters, aftermarket intake (e.g., BBK SSI), throttle body (80mm), or exhaust systems? What does the freeze frame data show on your OBD2 scanner—specifically ECT, MAP, MAF, IAT? Also, have you performed mechanical checks including fuel pressure and compression testing? Have you tried the carburetor spray test to identify potential vacuum leaks? (This is a critical step.)