Chevrolet Impala Limited check engine light on with low gas mileage and permanent code P0449 on Chevrolet Impala Limited

Some Chevrolet Impala Limited owners report experiencing issues related to the check engine light, low gas mileage, and a permanent trouble code P0449, indicating a problem within the EVAP system. This trouble code often points to a malfunction in the vent valve solenoid circuit, which can disrupt the purging of fuel gases. Owners may find this issue linked to a faulty valve solenoid, electrical problems, or a malfunctioning computer system, with repair costs varying significantly from $20 to $1,598. To address the check engine light, it is advised to pull the trouble code, identify and rectify the underlying issue, and then drive the vehicle until the problem is recognized as resolved. Additionally, low gas mileage may be attributed to difficulties with the fuel pump or a clogged fuel filter, necessitating further inspection. It is essential for owners to have their vehicle scanned to check for any codes indicating a lean condition that could contribute to both the low gas mileage and the P0449 trouble code.