There are 4 stored owner reports matching the powertrain & transmission leading-label group for the 2017 Mercedes-Benz CLA-Class in our NHTSA-sourced dataset. These are unverified consumer reports and may not reflect confirmed defects.
This group counts stored reports whose component label starts with one of this site's matching prefixes, ignoring case. Each matching report counts once within the group. Components mentioned later in the label or only in the narrative are not searched. How component counts work
Loaded 4 of 4 matching reports.
Open the full vehicle complaint log (all categories)Component or System That Failed or Malfunctioned: The component that failed was the partial-load ventilation valve, which is part of the engine’s crankcase ventilation system. This valve is responsible for regulating airflow and pressure within the crankcase during partial engine loads. A malfunction in this valve can lead to increased engine pressure, oil leaks, and potential damage to engine components. The component is still available for inspection upon request. Safety Risk: The failure of the partial-load ventilation valve put my safety, and that of others, at risk in the following ways: •Engine stalling or reduced power while driving, especially during acceleration, which increases the risk of an accident. •In some cases, oil leakage caused by excess crankcase pressure could lead to engine compartment smoke or a potential fire hazard. •If the engine performance is compromised, it may suddenly lose power on highways or intersections, posing a serious risk. Problem Reproduced or Confirmed: Yes, the issue was confirmed. The technician verified the faulty valve during a diagnostic inspection after I noticed performance issues and warning messages. Inspected by Manufacturer, Dealer, or Others: Yes, the vehicle was inspected Warning Lamps, Messages, or Other Symptoms: Yes, there were warning signs prior to the failure: •Check Engine Light illuminated on the dashboard. •Engine running rough or hesitating, particularly during acceleration.
Just replaced water pump and still need to replace positive Crankcase ventilation system hose
WHILE MAKING A U TURN ON FL-881 FOREST HILLS BLVD , THE HALF SHAFT FAILED, CAUSING TRANSMISSION TO DIS ENGAGE... WHILE ONCOMING TRAFFIC WAS HEADING TOWARD ME. ATTACHED COPY OF MAPS.
MAKING A U TURN , ON 3 LANE BLVD, A COMPLETE TRANSMISSION FAILURE HAPPENED AND COASTED TO HALT. UPON HALT, TRANSMISSION WOULD NOT ENGAGE, DRIVE OR REVERSE. HAD THERE BEEN HEAVY ON COMING TRAFFIC, I WOULD HAVE BEEN T-BONED CURRENTLY THE VEHICLE IS WITH DEALERSHIP UNDER REPAIR AND EVALUATION.
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.
NHTSA source checks for this vehicle year
Checks are recorded separately for each dataset, not for the whole page. Dates use UTC. A missing check date does not mean no records exist.
Vehicle import recorded: Aug 31, 2026. This is the stored import date, not confirmation that every source was successfully refreshed.