80 of the
305 complaints filed about the Mercedes Benz GLC300
are about the engine —
26% of everything owners reported.
The worst model year for it is 2016.
ENGINE AND ENGINE COOLING:ENGINE:OTHER FUEL TYPES:TURBO/SUPERCHARGER
Fuel Rail and fuel injectors Leak contacted Mercedes cooperate to investigate why my car. VIN did not list according to campaign no 2022030003 to replace the fuel Ra and fuel injectors and a Ssfety & Emissios recall campaign that covers 139 Model year 2016-2030 that include my vehicle CLC-Class. My car is experiencing fuel injectors defects but my VIN number was not flagged
NHTSA complaint #11659257 — an unverified report by a vehicle owner.
-The malfunctioned component is the Positive Crankcase Ventilation. - Vehicle wanted to stall and did not want to accelerate while in the middle lane on the highway with my family. - Yes it has been diagnosis by certified mechanic - The check engine light turned on at the time of the incident and has been turning on and off ever since.
NHTSA complaint #11654950 — an unverified report by a vehicle owner.
I was driving and my engine light came on. I ran the code and it came up as P052E which has to do with the positive crankcase ventilation regulator valve. I’ve heard that this part goes out very often on the Mercedes Benz.
NHTSA complaint #11651403 — an unverified report by a vehicle owner.
ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL:CRANKCASE (PCV)
The contact owns a 2016 Mercedes-Benz GLC300. The contact stated while driving at an undisclosed speed, the check engine warning illuminated. The contact stated that the vehicle was taken to the Emissions Center, and the vehicle failed the Emissions test. The vehicle was taken to the dealer to be diagnosed. The dealer retrieved DTC: P052E (PCM has detected an inappropriate degree of pressure from the crankcase pressure sensor). The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was unknown.
NHTSA complaint #11635618 — an unverified report by a vehicle owner.
The contact owns a 2017 Mercedes-Benz GLC300. The contact stated while driving at an undisclosed speed, the check engine warning light illuminated. The vehicle was taken back to the dealer and the contact was informed that the vehicle was repaired. The contact stated that the dealer had only reset the codes. In addition, the contact stated that the tire pressure sensor warning light was illuminated. The contact stated that the sunroof latch failed to close as needed using the sunroof power switch. The vehicle was not diagnosed or repaired by an independent mechanic or the dealer. The manufacturer was not made aware of the failure. The failure mileage was approximately 88,100.
NHTSA complaint #11626697 — an unverified report by a vehicle owner.
The contact owns a 2017 Mercedes-Benz GLC300. The contact stated while driving at an undisclosed speed, the accelerator pedal was depressed, however, the vehicle failed to accelerate as intended. In addition, the check engine warning light illuminated. The vehicle was taken to the dealer where it was diagnosed with a failed positive crank valve. The contact was informed that the positive crank valve needed to be replaced. In addition, the contact was informed that the repair was covered under an extended warranty program, however, the parts were on backorder. The vehicle was not repaired. The contact stated that the failure began in December 2023, however the warranty repair was completed in September 2024, due to parts being on back order. The vehicle was repaired, however, the failure reoccurred. The contact stated while driving at an undisclosed speed, the accelerator pedal was depressed, however, the vehicle failed to accelerate as intended. In addition, the contact heard a loud boom that came from the engine. The vehicle was taken to the dealer where it was diagnosed with a blocked turbo. The contact was informed that the turbo 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 94,000.
NHTSA complaint #11619914 — an unverified report by a vehicle owner.
The contact owns a 2016 Mercedes-Benz GLC300. The contact stated that while driving 45-50 MPH, the engine experienced rough idling and the vehicle was shaking violently. Several unknown warning lights were illuminated. The contact pulled over and turned off the vehicle. The vehicle was towed to an independent mechanic, who determined that cylinder #1 had a cracked piston and the engine needed to be replaced. The vehicle was then towed to another independent mechanic, who also determined that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure, but no assistance was provided. The failure mileage was approximately 90,000.
NHTSA complaint #11617878 — an unverified report by a vehicle owner.
Check engine light on-pvc failure. Code PO52E-71as determined by reliable repair shop. Recommended to have vehicle repaired by dealer. Shop advised part is vital to emissions system.
NHTSA complaint #11614470 — an unverified report by a vehicle owner.
ENGINE AND ENGINE COOLING:ENGINE:CRANK/CAMSHAFT POSITION SENSOR
The contact owns a 2016 Mercedes-Benz GLC300. The contact stated that while operating the vehicle, the check engine warning light remained illuminated. The vehicle was taken to the local mechanic who diagnosed that the crank case ventilation sensor was faulty and needed to be replaced. The vehicle was not repaired. The local dealer was not contacted. The manufacturer was notified of the failure, but no assistance was provided. The failure mileage was 70,000.
NHTSA complaint #11606449 — an unverified report by a vehicle owner.
When driving the car, the engine began to violently shake and fail. The engine ended up having a piston failure due to a small wrist pin and needed the entire engine block replaced. I was lucky that I was not on the freeway or in a more dangerous spot when the engine failed while driving.
NHTSA complaint #11606306 — an unverified report by a vehicle owner.
The contact owns a 2017 Mercedes-Benz GLC300. The contact stated that while at a stop light, the vehicle independently shifted to neutral(N) for approximately 5 minutes. The vehicle failed to release from neutral when the driver shifted the gear shifter. The contact stated that the transmission then released from neutral(N), and the vehicle jolted forward. The check engine warning light was illuminated. The vehicle was taken to an independent mechanic, who was unable to determine the cause of the failure. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was not contacted. The failure mileage was approximately 75,000.
NHTSA complaint #11595449 — an unverified report by a vehicle owner.
Diagnose: code P05271 - Positive Crankcase Ventilation Regulator Valve Performance: The valve for crankcase ventilation has a malfunction. Mercedes Benz extended warranty to 15 yr / 150k miles for intake assemble which resolve this issue. Like to acquire a confirmation letter from Benz to cover the repair by the Benz dealer
NHTSA complaint #11591965 — an unverified report by a vehicle owner.
Check Engine light came on. Mercedes Benz authorized service mechanic confirmed it is code P052E - Positive Crankcase Ventilation regulator valve issues that can cause engine to seize while driving. Vehicle has always been serviced regularly at authorized dealer service center. Current estimated Repair and replacement cost $9,700+ . Mercedes Benz authorized Service Center informed that the part is backordered and no estimated date available.
NHTSA complaint #11575152 — an unverified report by a vehicle owner.
Engine light. Told by Mercedes mechanic it is a code P052E - positive crankcase ventilation regulator valve issues that can cause engine to seize while driving. Repair cost $2,500+
NHTSA complaint #11574645 — an unverified report by a vehicle owner.
After noticing my engine light come on, I had my vehicle checked out, the dealer informed (after spending $250.00) that the problem is the crankcase ventilation and it's a common problem. It seems the oh so familiar crankcase ventilation system is not working. This is a common problem with the GLC300 and Mercedes Benz needs to correct it. The engine is not being ventilated properly and the overwhelming smell of gasoline engulfs the interior of the vehicle. This is putting mine and the life of my family at risk, due to a faulty manufacturer issue. Mecedes Benz needs to obviously correct the faulty parts they use as soon as possible, before someone loses their life.
NHTSA complaint #11563324 — an unverified report by a vehicle owner.
The P052E error has popped up which requires the replacement of the PVC assembly. This is a known issue with these engines and causes the engine to run erratically. Mercedes knows that the issue is common. Please investigate and issue a recall if applicable.
NHTSA complaint #11553798 — an unverified report by a vehicle owner.
I lost power on while driving at speed and almost got rear-ended before pulling over. I had to tow the car to a mechanic. After diagnosis it turned out the pistons are cracked and had to be replaced as well as the rod bearings. The pistons have a very abnormal burn pattern and rod bearing wear per my mechanic. This is a beautiful car and I take above average care of it. No car sold in the US should have pistons crack at such a short amount of miles. I believe Mercedes Benz should be held liable for their engineering error.
NHTSA complaint #11541304 — an unverified report by a vehicle owner.