2004 Chevy 2500 HD 6.0L Gas Engine Fault Codes P0154, P0155, P0161 After Hypertech Tuner Installation
I recently installed a Hypertech tuner on my 2004 Chevrolet 2500 HD with a 6.0L gasoline engine. Shortly after installation, the vehicle began experiencing engine misfires and triggered diagnostic trouble codes P0154, P0155, and P0161. I reverted to stock settings, and the engine now runs smoothly without any noticeable performance issues. However, the OBD2 codes persist even when the tuner is disconnected. The original operation was stable before the tuner was installed. I suspect the issue may be related to oxygen sensor B2 (S1 and S2) circuits or wiring faults. It's important to verify that all components are factory-original and that no other underlying issues exist.
The issue appears to be related to the Hypertech tuner affecting the oxygen sensors on bank 2, specifically sensors B2 S1 and S2. Check for wiring faults and ensure the heater circuits are functioning properly. Confirm that all components are stock and original equipment manufacturer (OEM) parts. Always recommend keeping the vehicle in stock configuration unless absolutely necessary—using OEM replacements is strongly advised to avoid such issues.