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.

- Sarasota, FL, USA

PVC valve indicator engine light keeps appearing after being replaced twice

- Decatur, GA, USA

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.

- Bath , NY, USA

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.

- Aliso Viejo, CA, USA

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

- Vernon, CT, USA

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.

- Tulsa, OK, USA

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.

- Whittier, CA, USA

2016 GLC300 - Fault code P052E71 positive crankcase ventilation regulatory valve displayed on console. I reset code and it came up again in a few days. Plaza Mercedes in St.Louis stated this is a common failure that requires digging deep into the engine. I had valve replaced 15SEP22 costing $1614.36. Invoice is attached.

- Saint Charles, MO, USA

Check Engine light P052E came on while driving. No collision, normal conditions other than first very cold night of the season. Looked it up and seems to be a common issue with this model.

- Brooklyn, NY, USA

Got the MIL obd2 error code P052E - Positive Crankcase Ventilation Regulator Valve Performance. After some research this seems to be a common issue for this vehicle and other similar Mercedes Benz vehicles with the same engine. It is something that it is extremely expensive to fix (2000) and very labor intensive. I believe that Mercedes Benz should recall these vehicles and replace the Intake line due to its constant failure on many vehicles including mine.

- Sequim, WA, USA

Crankcase ventilation valve issues

- Willow Grove , PA, USA

Got the MIL obd2 error code P052E - Positive Crankcase Ventilation Regulator Valve Performance. After some research this seems to be a common issue for this vehicle and other similar Mercedes Benz vehicles with the same engine. It is something that it is extremely expensive to fix (+$1500) and very labor intensive. I believe that Mercedes Benz should recall these vehicles and replace the Intake line due to its constant failure on many vehicles including mine.

- Cutler Bay, FL, USA

During normal highway driving, the check engine light energized in the display. At the same time, engine power was lost, and the vehicle could no longer accelerate. The Mercedes Benz dealership was less than a mile away, so I went directly there at a slow speed without damaging the engine. Upon inspection, the dealership found that the engine wiring harness was completely engine oil soaked and the oil drained down into the engine control unit (computer), causing loss of one of two turbochargers and loss of engine control and power. It is suspected that the oil originated from one or multiple of the camshaft sensors that are connected to the engine wiring harness. The engine oil traveled through the wiring harness and then completely soaked to engine control unit, which malfunctioned. If this happened while overtaking another vehicle or trying to avoid another, then I would have had a serious accident. I had insufficient engine power to avoid other cars and luckily was in the far-right lane to be able to exit the highway without an accident or damaging my engine due to the higher-than-normal rpms. The vehicle is currently at the dealership and requires a new engine wiring harness which may require removal of the engine to access and replace, a new engine control unit due to being engine oil soaked, and possibly a new turbocharger. This repair could cost well over $10,000 for parts and labor. The vehicle just had its annual maintenance service in September and no oil leak from the engine wiring harness was noted by technicians during the maintenance. The dealership continues to search and localize exactly where the oil originated but believes that either one or multiple camshaft sensors is the cause. The dealership does not know how long it will take to repair the vehicle due to the parts needed and the extent of labor that is required.

- Clarksburg, MD, USA

Piston 1 cracked while driving on the highway. My sibling was driving on the highway when the engine suddenly started misfiring and losing power because it lost compression on the piston that cracked. I was lucky enough that I have mechanic experience to replace all the damaged components myself and paid out of pocket. I was super fortunate that the cylinder walls did not get damaged when this happened thus not needing an entire engine replacement which would cost around $10,000 from mercedes. I had to go pick up a trailer from UHaul and go pick up the vehicle from where it broke down. Thinking about this from the perspective of a person who does not have access to rent a trailer, a vehicle to pull said trailer with, or the mechanic experience to fix the vehicle themselves, the cost to get this issue resolved would be much much more than it cost me.

- Burbank, IL, USA

While driving on the NYS Thruway last week, when I accelerated to pass another car, my engine bucked and kicked followed by the "check engine" light coming on.In very heavy traffic, I was able to pull to the shoulder. I called my service garage and they suggested I not drive the car for safety reasons. When the tow truck arrived, I briefly started the car with the same bucking and kicking from the engine. The car was taken to my regular garage where the "check engine" codes showed issues with the fuel injector and fuel injection system. I was told there is an existing RECALL CAMPAIGN # 2022030003 for the same year, make and model as mine but, my VIN is not part of that RECALL. I would like your help as I do not believe Mercedes-Benz is being fair or equitable in this RECALL. ThankYou

- Canandaigua, NY, USA

1)-The crankcase ventilation valve needs to be replaced. This seems to be common problem with these cars. 2)-No safety issues. 3)-Yes many failures as per the internet reports. 4)-Yes- Mercedes 5)-Unknown

- Hoschton, GA, USA

While operating the vehicle at highway speed, the Check Engine Light illuminated on the vehicle dashboard and remained constant. The associated malfunction code(s) displayed were P052E71 (actuator blocked) as well as P06DA00 (electrical-open circuit). The vehicle is available for inspection upon request. The vehicle emitted pungent odor and fumes into the cabin and demonstrated sudden decreased acceleration and rough idling. The problem has yet to be inspected by the manufacturer as it is not sure whether it is safe to operate. No other warning lamps illuminated prior to the failure. Unsure if cold start failure is a symptom associated with current issue or if an electrical problem related to prior recall.

- Clinton, MD, USA

Got a Check Engine Light at 32,400 miles and the code said it was the Positive Crankcase Ventilation Regulatory Valve. It was under warranty, the job requires over 6 hours of labor, and it's due to a intake breather valve getting gummed up with oil/oil vapors/condensation. Well, the check engine light came on again at 58,000 miles and 3 years later. Now not under warranty, the dealer quoted 6 hours and $1435 to do the same repair that was done before. The part is EXTREMELY difficult to get to in order to change, and requires the removal of many engine components, including one of the engine mounts. It seems like this is one of the most common repairs for this series of car. It's been so troublesome, that Mercedes has redesigned the part.

- Geneva, IL, USA

The vehicle engine amber light on, everything else looks like normally. Bring the vehicle to Mercedes dealership to diagnose and fix. After dealership fix, we find out this vehicle maximum speed is 61 during driving on the freeway and it cannot speed over 61. Also, the engine amber light is on again and seatbelt is not working well. We have safety concerns when driving this vehicle on the freeway. Thanks.

- Houston, TX, USA

At 40,000 miles, one of the wrist pins snapped and the piston broke off. This caused complete engine failure and the whole engine needs to be replaced. This is the same problem that caused a recall with the 2015 model. The dealership is making me pay for the labor, but Mercedes donated the engine (probably because they know it's their fault). So I'm wondering if there should be a recall on this model as well.

- Las Vegas, NV, USA