NHTSA complaint #11589176

Owner complaint summary

The contact owns a 2020 Mercedes-Benz GLC300. The contact stated that while driving at an undisclosed speed, the engine misfired. In addition, the check engine warning light was illuminated. The contact was turned off and restarted the vehicle. The contact stated that the vehicle drove as needed. The contact stated that the vehicle was taken to an independent mechanic however, the failure was unable to be duplicated. The vehicle was not repaired. The contact stated that the failure occurred intermittently for several months. The vehicle was taken back to the independent mechanic where it was diagnosed with a failed engine vent seat and the engine vent seat needed to be replaced. The vehicle was not repaired. The contact was advised to take the vehicle to the dealer. The vehicle was taken to the dealer where it was diagnosed with a failed engine vent seat and the engine vent seat needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure and a case was filed. The failure mileage was approximately 25,000.