2018 Mercedes-Benz GLC 300 engine problems

Filed Jul 30, 2026 · Engine · NJ

Error code P052E71 on a 2018 Mercedes-Benz GLC 300 4MATIC means the Positive Crankcase Ventilation (PCV) Regulator Valve Performance has a malfunction, specifically that the partial-load ventilation valve actuator is blocked. By research, i found that this is a very common problem on those engines, and no recalls from the company to fix their fault.

Filed Jun 3, 2026 · Engine, Transmission · CA

Component Failure: The vehicle is equipped with the M274 2.0L turbocharged engine, which suffered a major internal mechanical defect. An authorized Mercedes-Benz dealership diagnosed the vehicle at 79,504 miles with a malfunction in the crankcase ventilation system alongside severe internal defects, quoting a total repair estimate of $9,851 to perform extensive engine work. Safety Risk: This known manufacturing defect involves premature failure and cracking of the pistons, which poses an immediate safety hazard due to potential catastrophic engine failure and sudden, complete loss of motor power while driving at highway speeds. The manufacturer has failed to offer an extended warranty or recall for this known issue on the 2018 model year.

Filed Nov 6, 2025 · Electrical, Engine · AL

I had the engine light come on and took it to the dealership. They quoted me over 8 thousand dollars to fix. I took it to a repair shop that works on luxury cars and they fixed it for less than 1000 dollars. I had to have the transducer fixed in the turbo in my engine and when they did that they found oil in the electrical harness. That was caused by the oil seperator. They told me that it was a manufacture defect that has been well documented and to take it back to Mercedees Benz. They looked and found the oil but said my car did not produce a code and could not fix it. We escalated it to corporate that reviewed my case and said they still would not fix until it produced a code. Mercedees implemented an extended warranty for my car back in 2022 for emissions. They said they would cover it if it produces a code. I researched this problem and it said it posses a risk to me, my passengers and the public if it quits running or causes a fire. Corporate said its not a problem yet.

Filed Jul 28, 2025 · Acceleration, Engine · CA

The car does not go into drive from reverse and will sometime automatically shift itself from a low drive gear (D1) into Neutral without warning. After this happens - the car also can't get back into D1. It takes about 20 seconds for the car to shift back into a Drive gear and it will jolt into D3 violently. This has been a scary experience on many occassions - especially at red lights when this happens and we can't get the car out of neutral for some time. This was diagnosed by mercedes dealership near us as a fawlty sensor in the transmission. It is extremely expensive to fix and is specific to mercedes meaning it has to be done by a MB dealership. We applied for good will for assistance but were denied. The car has been maintained very well - this is not a maintenance issue but a specific sensor failure of a mercedes sensor in the transmission. We are thankful no one was hurt - we had our 8 year old daughter in the car when stalling out several times at red lights and it's been a very scary situation.

Filed Dec 16, 2024 · Engine · GA

I have engine light on and when I scanned it, I got a error code P052E For crankcase vent valve issues. It is most common problem with Mercedes-Benz Glc .

Filed Jun 4, 2024 · Driver assistance, Engine · NY

when the car is in drive it will stop like it is in park unable to drive or put in reverse. This happens at random times on the road. The car will then skip gears and go into Neutral then skip an again on its own and go into drive.

Filed Mar 29, 2024 · Engine · FL

Vehicle showing check engine light, connected a reader to the vehicle and it shows a code of P052E .. ( Positive Crankcase Ventilation Regulator)

Filed Mar 26, 2024 · Electrical, Engine · NY

I brought my vehicle in to get serviced because the check engine light came on and I was told it was CODE PRESENT P0521E71 VALVE FOR CRANK CASE VENT. HAS MALFUNCTION / BLOCKED. I was told I have warranty on it so Mercedes of Massapequa took the car to fix.I was told the part was fixed but oil was found on my engine computer from the crank case vent malfunctioning but the warranty won't cover it although it was a direct result of a part that was covered part and had caused the damage.They gave me my car back and my car is worse it has problems starting it requires multiple cranks and the air conditioner has a fuel smell when turned on and I am unable to pass my vehicle inspection because my check engine light it still on.I spoke to the corporate office and they said because I have too many miles they can't do a courtesy and honor the cost and referred me back to the dealer and the dealer told me they will bring the cost to fix the computer leak to $6000 although it was due to a faulty part on their behalf .I am beyond upset my car is non longer reliable or safe to drive.Mercedes of massapequa ignored all my calls after they gave me back my vehicle that was worse after they claimed they fixed it.

Filed Mar 7, 2024 · Engine, Fuel system · TX

Car failed to accelerate due to faulty fuel pump, fuel tank, etc. Car stopped and died several times in the middle of heavy traffic. Mercedes Benz of West Houston, Sewell Dealership, has my car that was towed to them late afternoon on 3/5/2024. I have owned a Mercedes for over 40 years and never had this occur or be scared due to the car’s lack of performance.

Filed Jan 21, 2024 · Engine · LA

Engine light error code P-052e71. The crankcase ventilation valve malfunction. This is reported by a lot of customers.. It cost about $2000 to fix this problem.