Mercedes Benz

Okay, let's break down those **P0440** and **P0441** trouble codes. These are OBD-II diagnostic trouble codes related to your vehicle's evaporative emissions control system – specifically the EVAP (Evaporative Emissions Control System) Fuel Tank Ventilation System. They indicate a problem with the fuel vapor management system, although the specific description "Above Limit" adds an interesting nuance: ### **P0440: Fuel Tank Ventilation System - Above Limit** *   This is a general code indicating that your car's computer (PCM or ECM) has detected a fault condition in one of its sensors related to the EVAP system. The specific meaning can vary slightly by manufacturer, but "Above Limit" typically refers to an issue with **pressure**.     *   It often means the fuel tank pressure is higher than expected during normal operation (e.g., when the system should be venting or purging). This could indicate a blockage in the EVAP system where vapors aren't bein...