What 29 owners told NHTSA about the 2018 Mercedes-benz S-class Hybrid

Excessive engine oil lead from the back seal. Also, slow coolant leak. The car has a low mileage of 46k.

NHTSA ODI 11713255

My 2018 S560 Mercedes occasionally misfires upon acceleration. This has happened at six times over the past three years. When this happens, the engine loses power, starts to shake, and the check engine light comes on. This happened when I was trying to pass a car on US 301 a week ago nearly causing a head on collision as I tried to get back into the right lane. The problem occurs without any warning. This first happened at 64,242 miles, then at 104833, next 108599, then 119,012, then 121,726, and finally at 126580 (my current mileage). Each time I have gone to a Mercedes mechanic. They have replaced the coils three times and the spark plugs twice. They now tell me the problem is due to the walls of the cylinders delaminating and scratched/scoring and the engine needs replaced (come on, 126,000 miles). They have checked the compression and say it is low across all eight cylinders. The vehicle has been inspected by a Mercedes dealership and by other certified Mercedes mechanics. They gave me pictures of the cylinders (attached). Here are their notes: Cylinder walls in #1 look delaminated, also scratched, no signs of oil consumption on spark plug, carbon is burnt off #1 piston in center. Preformed compression test on cylinder 1 and 2, #1 dry 140, wet 170, #2 dry 110, wet 170. Just these 2 cylinders are showing leakage past rings, luckily no oil consumption. Compression spec's13 to 17 Bar{ 188 psi to 246 psi } Cylinder #1 dry 160psi, wet 190 psi, Cyl #2 dry 150psi wet 185psi, #3 160psi dry, wet 190psi, Cyl #4 160psi dry, wet 190 psi, Cyl #5 155psi dry, wet 190psi, Cyl #6 155 dry, wet 190, Cyl #7 155 psi dry, wet 180psi, Cyl #8 160psi dry, wet 185psi. All wet and dry actual compression are all too low, likely from the cylinder wall conditions. Being compression is low across all cylinders this is causing misfires at random times across all cylinders.

NHTSA ODI 11664290

The engine failed while my friend was driving. The car is available for inspection. My friend almost got into a car accident because the car started shaking and the steering wheel closed up before the engine completely failed. Additionally, the airbags did not go off. It could've been a fatal accident because he was driving on the highway. The problem was confirmed by an independent service center. The vehicle has been inspected by a certified mechanic. The car has had problems since I bought it. The tire pressure would always go down. The steering wheel and car would shake at times, and the tires had to be replaced two times within two years.

NHTSA ODI 11609520

Ignition coil failed and cylinder 5 misfired. Car has less than 30K miles.

NHTSA ODI 11549938

Walk Home Condition -I purchased a 2018 CPO Mercedes-Benz S560 on 8/20/21 from Knauz Continental Autos in Lake Bluff, IL. On 9/25/2, at approx noon, I was driving the vehicle and the engine light came on, the throttle/engine felt sluggish and not responsive. The engine felt very out of balance shaking the entire care when the gas pedal was pressed. 5 mins later in heavy traffic, I stopped at a light, the engine started violently shaking and stalled. I shut the car off and tried to start it over a 5 min period. I was able to limp the vehicle to a local Mercedes dealership (Bloomfield, MI). Could only operate the vehicle below 25 MPH without violently shaking. The dealership was only 1 mile away. That dealership was able to quickly check codes. When I arrived the engine light went out and no codes where set. The assistant Service Manager told me that it looked like cylinder 4 was misfiring, but no code set. He told me that if it happens again, shut the car off and it should reset. I left the dealership around 1pm and continued driving. The issue had stopped. Approx 5 hours later, after driving for 3 hours, the same issue happened again about 5 miles from my home. The vehicle stalled multiple times and I finally got it running and limped the vehicle home at 20-25 MPH. The engine fault light stayed on this time. I let the vehicle sit in my garage on 9/26/21 as I was afraid to drive it anywhere. On 9/27/21 I drove the vehicle to the dealership close to my house. (Rochester Hills, MI) When I submitted the vehicle I was told that because I didn't have an appointment, they weren't sure if they could look at it that day. Service Rep called and said that the vehicle set a code (P030485). They said it would probably go away so I picked it up. Same issue occurred on 9/29/21 after driving for 25 mins. Had to limp the vehicle home again at 20 MPH. I turned the vehicle back into the same dealer on 9/30/21. I have zero visibility on a fix and next steps.

NHTSA ODI 11435904

2018 MERCEDES BENZ S CLASS. CONSUMER WRITES IN REGARDS TO REWORK ENGINE OIL PLUGS SAFETY RECALL. *LD THE CONSUMER STATED THE MANUFACTURER EXCEEDED A REASONABLE AMOUNT OF TIME COMPLETING THE RECALL REPAIR. *JS THE CONSUMER STATED THE VEHICLE WAS REPAIRED. *JS

NHTSA ODI 11349483

TL* THE CONSUMER OWNED A 2018 MERCEDES-BENZ S560. AFTER DRIVING THE VEHICLE FOR APPROXIMATELY THREE MINUTES, THE CONTACT PARKED THE VEHICLE. THE CONSUMER WAS ALERTED BY SOMEONE THAT THERE WAS SMOKE UNDER THE HOOD OF THE VEHICLE. WITHIN THIRTY SECONDS TO A MINUTE, THE VEHICLE BECAME ENGULFED IN FLAMES. THE FIRE DEPARTMENT WAS NOTIFIED AND EXTINGUISHED THE FIRE. THE ENGINE COMPARTMENT AND VEHICLE WERE DESTROYED. POLICE AND FIRE REPORTS WERE FILED. THERE WERE NO INJURIES. THE VEHICLE WAS TOWED TO MERCEDES-BENZ OF CALDWELL (1220 BLOOMFIELD AVE, WEST CALDWELL, NJ 07006, (973) 227-3600) TO BE INSPECTED. THE VEHICLE WAS NOT DIAGNOSED OR REPAIRED. THE MANUFACTURER WAS INFORMED OF THE FAILURE. THE APPROXIMATE FAILURE MILEAGE WAS 39,000. *LN*JB *AS

NHTSA ODI 11278598