Which parts fail
Components named in complaints (engine, cooling system, oil leaks, timing chain, exhaust).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2012 Mercedes-Benz E350 owners, lightly cleaned up (personal details are redacted by NHTSA).
The contact owns a 2012 Mercedes-Benz E-350. The contact stated that while attempting to start the vehicle, the check engine warning light illuminated. The vehicle was taken to an independent mechanic where it was diagnosed with a failed crankshaft sensor. The contact stated that the crankshaft sensor was replaced; however, the failure reoccurred. The vehicle was taken to another independent mechanic where the contact was informed that the crank shaft sensor needed to be replaced. The vehicle was repaired; however, the failure reoccurred. The vehicle was taken to another independent mechanic, and the crankshaft sensor was replaced. The vehicle was repaired, but the failure reoccurred. 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 152,000.
The contact owns a 2012 Mercedes-Benz E350. The contact stated that after retrieving the vehicle from the dealer, the check engine warning light was illuminated. The vehicle was taken back to the dealer where it was diagnosed that there was oil contamination through the camshaft sensor. The contact was informed that the engine wiring harness needed to be replaced. The vehicle was not repaired. The vehicle was taken to an independent mechanic for confirmation of the diagnosis. The manufacturer was notified of the failure. The approximate failure mileage was 54,700. The VIN was not provided.
The contact owns a 2012 Mercedes-Benz E350.The contact stated that while driving approximately 30 MPH, the vehicle started to jolt forward. Upon shifting to fourth gear, the vehicle stopped jolting. While depressing the brake pedal, the vehicle jolted. There were no warning lights illuminated. The vehicle was taken to the local dealer where it was diagnosed that oil was leaking into the engine and the wiring harness. The vehicle was not repaired. The manufacturer was made aware of the failure and referred the contact to the NHTSA Hotline. The failure mileage was approximately 82,000.
[redacted].The engine intake manifold on our 2012 Mercedes E350 (64,000 miles) EXPLODED with enough force to bend the hood up 2 inches. It was a damp cold morning & the engine had not been started in 12 hours. The car was not locked & the key fob was nowhere close. The fuel level was under 3/4 full. This happened when wife went to get something out of the car and when she pulled the passenger door handle to open - B O O M !!!! If this happened 30 minutes later, I would have been under that hood checking the fluid levels for a trip to San Francisco. I WOULD HAVE BEEN SERIOUSLY HURT OR KILLED!. It was towed to Mercedes-Benz of Carlsbad, Carlsbad California on [redacted] & they have not been able to identify the cause. They could replace the broken parts at the cost of $8,000 but that doesn't fix the problem. And if it happens again & hurts or kills someone, they could be held liable. …
My check engine light has been on for about a year, I have been told by both the dealerships here in Memphis/Collierville that as long as the light is an orange color there is nothing to worry about but it has been on consistently for about a year. I had a Diagnostic test done on [redacted] by Dr. Benz Affordable Mercedes Benz care and it was revealed that ME control module, oxygen sensor, engine wiring harness has oil intrusion all throughout. I would hate to attempt to drive my vehicle and all of a sudden it is severely damaged because of this. I feel this may be a very costly expense and would like some assistance in taking care of this matter. I love my car and have not had any problems, and hope to have it several years more. I only have 116,038 miles on this 2012 vehicle that I purchased in 2015
Cam adjustment solenoids leak oil into the engine wiring harness causing component failures, rough running and stalling. This problem was diagnosed and replaced by the dealer at 48k miles and has returned at 116k miles. There is a recall for models prior to 2012 and this car has the same problem. Eventually the engine will quit running at any given moment posing a dangerous situation.
Camshaft sensors and solenoid leak oil internally which then gets into the sensors electrical connector. From the the oil enters the engine wire harness through capillary action maki g it's way to other sensors and ultimately the DME (Digital Motor Electronics). This can cause February DME to fail which in turn can make the engine stop running.
Hello, A manufacturer should understand that Timing Chain is a vital component in an engine, an so should not say just tell consumer that it goes bad at a particular milage., As such in my MB E350 2012, is difficult to start the car and i think that this should be looked at. Thanks
Recall exists related to a potential issue with the high-pressure fuel pump, which could lead to engine stalling and increase crash risk. My 2012 Mercedes E350 stops the engine in the middle of the road couple of times and for some reason, its stops or shut off the engine completely. The last time I was pulling out on the main road and stop right there. I made a big traffic, and I was scared because I cannot start the car. The guy stops and help me to push out of the road, but we cannot push the vehicle unless someone is inside the car. If I go out, it will automatically go on "park" and cannot push the car. When you check the dashboard the check engine light is not on. …
While driving on an express way in dallas, texas my GPS made an error concerning an exit and I was required to divert quickly to the left to make exit lane .time was 6:00 pm ,heavy traffic conditions and road and weather conditions were excellent and dry. My Mercedes pre activated a skid mode and there was approximately a 70% cut back in engine power .a yellow engine light came on and skid mode came on operator screen but there was no skidding taking place. I was helpless with no power to keep up with the 50-60 MPH traffic while trying to get into lane .consequently a semi tractor struck my left rear fender /bumper causing damage to my Mercedes. There was no damage to the tractor. According to Mercedes the vehicle was supposed to do this as a safety feature. …
Engine complaints in other E350 years
Frequently asked questions
How common are engine problems on the 2012 Mercedes-Benz E350?
NHTSA has 21 complaints about the engine & cooling of the 2012 Mercedes-Benz E350, 10% of the model year's 217 complaints. The component named most often is engine › crank/camshaft position sensor (1 mentions).
Is there a recall for 2012 Mercedes-Benz E350 engine problems?
No. NHTSA lists no engine & cooling recall for the 2012 Mercedes-Benz E350, though it has 7 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2012 Mercedes-Benz E350 engine problems start?
Half of the complaints with a recorded mileage happened before about 82,000 miles, and 25% before 25,000 miles.
Is it dangerous?
Owners linked 2 crashes, 1 fire and 1 injury to engine & cooling problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.