GMC Sierra 2500 HD recurring emissions system problem on GMC Sierra 2500 HD

Some GMC Sierra 2500 HD owners report experiencing recurring emissions system problems that can affect vehicle efficiency and environmental compliance. These issues may manifest as a "Service Emissions System" message, indicating potential malfunctions that require immediate attention. Additionally, owners often notice warning signs such as check engine lights and error codes like P0422, which are crucial for diagnosing emissions-related issues. GM has acknowledged these concerns and issued fixes for the 2024 GMC Sierra HD to correct glitches in the Electronic Control Module that may lead to incorrect emissions data during testing. It is recommended that affected owners work closely with authorized GMC service centers to accurately diagnose and repair these emissions system problems, ensuring optimal performance and compliance with environmental standards.