GMC Envoy XL intermittent trembling and stalling issue despite recent tune-up on GMC Envoy XL

Some GMC Envoy XL owners report experiencing intermittent trembling and stalling issues despite having recently performed a tune-up. These problems may be attributed to fuel issues, such as bad gas or water in the gas tank, which can cause the engine to run rough and stall. Additionally, a dirty or faulty Idle Air Control (IAC) valve may lead to stalling at idle, as it regulates airflow into the engine. Some owners also notice that turning on the A/C causes engine RPM fluctuations, indicating potential problems with the A/C system or other underlying engine performance issues. Furthermore, electrical grounding issues, particularly a bad ground for the fuel pump assembly, have been linked to similar stalling problems. It is advisable for owners experiencing these symptoms to consult a mechanic for a thorough inspection of these areas to identify and resolve the underlying issues.