Mercedes-Benz CLA250 crankcase vent valve hose oil leak issue requiring line replacement on Mercedes-Benz CLA250

Some Mercedes-Benz CLA250 owners report experiencing oil leaks due to a brittle crankcase vent valve hose, which can worsen with temperature changes. These leaks may necessitate the replacement of the entire crankcase vent line assembly, and Mercedes-Benz recommends changing the crankcase vent valve every 50,000 miles to maintain engine reliability. Although the crankcase vent line assembly is covered under the Mercedes-Benz Emission Extended Warranty for 15 years or 150,000 miles, repair costs can still be significant, with estimates around $2,000 for parts and labor. Additionally, some owners face issues related to a malfunctioning PCV valve, which is a wear item that requires periodic replacement to ensure proper functioning of the Positive Crankcase Ventilation system. It is crucial for owners to address these oil leaks promptly to prevent potential engine damage and maintain the performance of their CLA250.