Po52E71- Emissions issue with crankcase. Mercedes implemented an extended warranty on various models but excluded 2019 C300, which definitely has the same issues. See below in reference to previous models. IMPORTANT EMISSION EXTENDED WARRANTY INFORMATION In our continuing efforts to assure the proper performance of Mercedes-Benz products and to enhance the satisfaction of our customers, Mercedes-Benz USA, LLC (MBUSA) is extending the warranty coverage on the intake line assembly in certain Model Year (MY) vehicles listed below from the original New Vehicle Limited Warranty of 4 years/50,000 miles to 15 years/150,000 miles (whichever occurs first) due to the following condition: ¢ Under certain circumstances, the partial-load ventilation valve (a part of the intake line assembly) may not work as intended, resulting in the illumination of the check engine Malfunction Indicator Lamp (MIL). A faulty partial-load ventilation valve might also increase exhaust gas emission. Model Model Years Sales Designation C-Class 2015 ‘ 2018 C 300, C 300 4MATIC C-Class Convertible 2017 ‘ 2018 C 300 Convertible, C 300 4MATIC Convertible C-Class Coupe 2017 ‘ 2018 C 300 Coupe, C 300 4MATIC Coupe C-Class Hybrid 2016 ‘ 2018 C 350e E-Class 2017 ‘ 2019 E 300, E 300 4MATIC GLC 2016 ‘ 2019 GLC 300, GLC 300 4MATIC GLC Coupe 2017 ‘ 2019 GLC 300 4MATIC Coupe GLC Hybrid 2018 ‘ 2020 GLC 350e 4MATIC SLC 2017 ‘ 2020 SLC 300 SLK 2016 SLK 300