Some Chevrolet Cobalt owners report experiencing stalling issues at stop signs and during idling, often accompanied by fluctuating RPMs. These problems may be attributed to fuel issues, such as bad gas or water in the gas tank, which can lead to rough engine performance and stalling. Additionally, some owners have encountered difficulties related to components like the mass airflow sensor and throttle body, which may not resolve even after maintenance like tune-ups and cleaning. Problems with the idle system, including a bad coil pack, can also contribute to stalling during idling situations. Cleaning the air filter housing and throttle body has been reported to help improve stalling issues for some owners. Symptoms associated with stalling may include dimming lights and weak power steering, indicating a drop in idle speed. Addressing these potential causes may be essential for effectively resolving stalling issues in the Chevrolet Cobalt.