There are 9 owner-reported engine complaints for the 2019 Mercedes-Benz C-Classin NHTSA's database. These are unverified consumer reports and may not reflect confirmed defects.
While driving on highway, the engine light came on, a diagnostic test was performed by dealer, oil control valve defected) This could cause engine to lock up while driving, a serious safety concern. I contacted Mercedes Benz corporate office seeking help, because of factory defect. They're not assisting me with this extreme safety matter!!
The fuel hose on the right hand side of the vehicle is leaking onto my engine. You can easily see this leak and smell it when unlocking the car in the morning. It is dangerous and could easily result in a fire.
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
The contact owns a 2019 Mercedes-Benz C300. The contact stated that the "Service Engine Soon" warning light was illuminated. The contact restarted the vehicle several times; however, the warning light remained illuminated. The vehicle was taken to an independent mechanic who retrieved DTC code: P0600 -which was related to the secondary oil pump. The vehicle was then taken to another dealer where the contact was informed that the vehicle could be repaired at that location; however, the contact was later informed that the dealer did not have the part needed to service the vehicle and referred the contact to another dealer. The vehicle was taken to a dealer where another diagnostic test was performed, and the dealer confirmed the failure. The contact was provided an estimate for the repair but declined the repair. The vehicle was not repaired. The manufacturer was notified of the failure but offered no assistance. The failure mileage was approximately 32,000.
When depressing the throttle, occasionally there is no response form the engine or a significant delay coupled with erratic engine revving behavior. When this happens the car has no drive power, but power brakes and steering are unaffected. The engine sits at idle speed. This has happened on multiple occasions when in or crossing traffic. The issue may present and then disappear after 15-45 seconds with no other action being taken.
TL* THE CONTACT OWNS A 2019 MERCEDES-BENZ C300. THE CONTACT STATED WHILE STATIONARY, THE VEHICLE SHUTOFF WITHOUT WARNING. THE CONTACT WAS ABLE TO RESTART THE VEHICLE. THE VEHICLE WAS TAKEN TO THE LOCAL DEALER KEYES EUROPEAN (5400 VAN NUYS BLVD, SHERMAN OAKS, CA 91401 (818) 574-5053) WHERE IT WAS DIAGNOSED WITH NO FAILURES. THE VEHICLE WAS NOT REPAIRED. THE MANUFACTURER WAS INFORMED OF FAILURE AND INFORMED THE CONTACT TO TAKE THE VEHICLE TO BE REPAIRED. THE FAILURE MILEAGE WAS APPROXIMATELY 4,700. ## VIN PASSED ## MERCEDES-BENZ 2019 C300 ##
TL* THE CONTACT LEASED A 2019 MERCEDES-BENZ C300. THE CONTACT STATED THAT WHILE DRIVING AT 70 MPH, THE VEHICLE DECELERATED INDEPENDENTLY TO 30 MPH WITH THE CHECK ENGINE WARNING LIGHT ILLUMINATED. THE FAILURE WAS EXPERIENCED THREE TIMES. THE VEHICLE WAS TOWED TO THREE UNKNOWN DEALERS WHERE THE VEHICLE WAS DIAGNOSED AND THE CONTACT WAS INFORMED THAT THE HIGH-PRESSURE FUEL PUMP NEEDED TO BE REPLACED. THE ECM WAS ALSO REPLACED HOWEVER, THE REPAIR FAILED TO FIX THE FAILURE. THE VEHICLE WAS NOT REPAIRED. THE FAILURE MILEAGE WAS 6,000.
TL* THE CONTACT OWNS A 2019 MERCEDES-BENZ C300. WHILE DRIVING APPROXIMATELY 35 MPH, THE VEHICLE UNEXPECTEDLY SHUT OFF WITHOUT WARNING. THE VEHICLE WAS TOWED TO EURO MOTORCARS BETHESDA (7020 ARLINGTON RD, BETHESDA, MD 20814) FOR DIAGNOSTIC TESTING, BUT THE CAUSE OF THE FAILURE COULD NOT BE DETERMINED. THE VEHICLE WAS NOT REPAIRED. THE MANUFACTURER WAS NOT NOTIFIED OF THE FAILURE. THE FAILURE MILEAGE WAS 1,250. THE VIN WAS UNKNOWN.
TL* THE CONTACT OWNS A 2019 MERCEDES-BENZ C300W. THE CONTACT PURCHASED THE VEHICLE ON APRIL 6, 2019. ON APRIL 10, 2019 HE TOOK THE VEHICLE BACK TO THE DEALER (MERCEDES-BENZ OF SARASOTA, 4754 CLARK RD, SARASOTA, FL 34233, (941) 275-1293) BECAUSE IT SHOOK VIOLENTLY WHILE DRIVING AND THE ENGINE FELT LIKE IT WAS LOSING POWER AT 20 MPH. ALSO, AN ABNORMAL NOISE WAS HEARD. THE DEALER STATED THAT THE FAILURES WERE NOT ABNORMAL. THE DEALER TEST DROVE THE VEHICLE WITH THE WINDOWS UP AND COULD NOT REPLICATE THE FAILURES; HOWEVER, THEY STATED THAT THE NOISE WAS DUE TO A DESIGN FAULT THAT OCCURRED WHEN THE REAR WINDOWS WERE OPEN. THE CONTACT SPOKE WITH THE STATE ATTORNEY GENERAL'S OFFICE AND WAS ADVISED TO PURSUE HIS CONCERN UNDER THE STATE LEMON LAW. THE CONTACT CALLED THE MANUFACTURER AND WAS INFORMED THAT THE CASE WOULD BE ASSIGNED TO A CASE MANAGER AND HE WOULD BE CALLED BACK WITHIN 24 HOURS. IF THE ISSUE COULD NOT BE RESOLVED, THE CASE WOULD BE TURNED OVER TO AN EXECUTIVE INVESTIGATING SQUAD. THE DEALER CALLED THE CONTACT AND ASKED FOR A CALL BACK. AFTER SEVERAL ATTEMPTS TO CALL THE DEALER, THE CONTACT HAD NOT HEARD BACK. THE FAILURE MILEAGE WAS 1,700. *BF *JB
Complaints are unverified consumer reports submitted to NHTSA. A high complaint count may reflect vehicle popularity, not defect severity. Data sourced from NHTSA public records.
Data synced from NHTSA on Apr 25, 2026