Kia Forte rough engine idle issue when A/C is on, alternator pulley replaced on Kia Forte

Some Kia Forte owners report experiencing rough engine idle issues, particularly when the A/C is on. These problems may be linked to the check engine light being illuminated, prompting the need to check for OBD II codes to identify specific issues. Additionally, owners are advised to inspect plugs, air filters, and vacuum hoses for signs of damage or wear. If the alternator pulley has been replaced but rough idling persists, it is crucial to verify that the replacement was done correctly and that the new pulley is functioning properly. Monitoring the alternator's voltage readings during idle and while accelerating is also recommended to ensure they are within the appropriate range. Furthermore, checking the condition and connections of all wires leading to the battery can help prevent electrical issues that may contribute to rough idling. Lastly, some owners find it beneficial to have their mechanic inspect engine and transmission mounts for looseness, as this could cause vibrations during idle, especially with the A/C running.