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10.0

really awful
Crashes / Fires:
2 / 1
Injuries / Deaths:
1 / 0
Average Mileage:
40,631 miles

About These NHTSA Complaints:

This data is from the NHTSA — the US gov't agency tasked with vehicle safety. Complaints are spread across multiple & redundant categories, & are not organized by problem.

So how do you find out what problems are occurring? For this NHTSA complaint data, the only way is to read through the comments below. Any duplicates or errors? It's not us.

2012 Mercedes-Benz E350 engine problems

engine problem

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2012 Mercedes-Benz E350 Owner Comments

problem #15

Sep 072022

E350

  • miles

A D V E R T I S E M E N T S

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.

- Milpitas , CA, USA

problem #14

Nov 192021

E350

  • 54,700 miles
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.

- Gardnerville, NV, USA

problem #13

Oct 302021

E350

  • miles
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.

- Dallas, TX, USA

problem #12

Mar 262021

E350

  • 101,000 miles

A D V E R T I S E M E N T S

My 2012 Mercedes E350 has oil contamination of the wiring harness. The oil has also damaged other components in the engine compartment including oxygen sensors; probes and ECU(computer) this is very expensive damage. Mercedes-Benz had had recall for this problem in the past but the recall did not extend to the 2012 model year. They need to do another recall for this ongoing problem. This is a major safety hazard, as the car could stall in traffic without warning

- Flower Mound, TX, USA

problem #11

Mar 052021

E350

  • miles
The car shuts off randomly at stop lights. I cannot tell it is off until we are a green light and then I have to start the car. Cars behind me have almost hit

- South Elgin, IL, USA

problem #10

May 152019

E350

  • miles
The cam solenoid sensors are picking up oil, then it is being disbursed in to the electrical systems of the vehicle. It is flowing into, O2 sensors making the vehicle run in a full rich mode, it is reaching the computer system that runs the entire vehicle. This repair can cost upwards of $8000. I have done online research and it is a very common issue amongst many Mercedes vehicles. The issue is a known problem, it was being repaired but Mercedes stopped the repair. It comes from an internal issue, not a fail to maintain problem. I contacted Mercedes, they say they don't know of the issue, but they did tell me, they know how to fix the problem for a cost of over $ 5000. To us. Online searches have resulted in many complaints by owners. Regular driving is a result of the issue. Now we can't drive out vehicle due to fear of the oil in the electrical lines reaching our cpu for the entire car, which will result several thousand more dollars on top of the repair cost. We have paid $ 800. At this point only to be told, do not drive the care or worse damage will occur. So we have a beautiful car that is collecting leaves and dust. I await your response, garyw. Smith. We contacted Mercedes bens of raleigh nc, they are our contact point, they don;T know of an issue but know the cure for $5000. Plus dollars, hmmm, curious...

- Broadway, NC, USA

problem #9

Jun 222020

E350

  • 87,000 miles

A D V E R T I S E M E N T S

The contact owns a 2012 Mercedes-Benz E350. The contact stated that at start-up, the check engine warning light illuminated. The vehicle was taken to Mercedes-Benz of sacramento (1810 howe ave, sacramento, ca 95825) where the vehicle was diagnosed with a defective O2 sensor. The contact stated that before agreeing to the repair, he requested that the mechanic inspect the camshaft sensor for a possible link to the failure. The contact was informed that failure had in fact started with the defective camshaft sensor and spread to the O2 sensors and wiring harness. The contact was then given an estimate for the repairs. The manufacturer had been notified of failure and offered financial assistance for the repair but offered no additional assistance. The repair was still pending. The failure mileage was 87,000.

- Sacramento, CA, USA

problem #8

Dec 022019

E350 6-cyl

  • 89,000 miles
'experienced rattling sounds and took vehicle for inspection to Mercedes-Benz of tucson (mbt) on 5/9/18 'inspection found secondary chain tensioners producing rattling noise until oil pressure is built up. Est cost of repairs $1497.94. Receipt reads: No consequential damage to be expected 'July 2018 check engine light. Autohaus tucson found engine light related to damaged temp sensor wiring; repaired pack rat damage wiring for ambient temp sensor 'Oct 2019 check engine light on; mbt inspection; diagnosis: Fault code #P001685-position of intake camshaft is implausible to the position of the crankshaft bank 1; engine out of time due to cam adjuster failure 'mbt stated that they could start repairs until after 11/18/19 as the specialty tech was unavailable 'contacted mbt regularly until they were able to take vehicle in on 12/2/19. 'to date, vehicle has been in the possession of mbt for 119 days 'cost and diagnosis have grown exponentially from $1497 to a whopping $12,000 for extensive engine repairs! 'mbt stated that after repairs were completed, the engine did not operate properly, and they would need to 'break the engine down' again to find the problem 'found the engine was cracked and the cost reflect problems found inside the engine after subsequent repairs were completed 'I have maintained regular maintenance schedules and question whether such damages result from neglect on the part of Mercedes Benz of tucson or of a manufacturing flaw of the 2012 E350 engine. Neither is satisfactory 'to date, mbt have not supplied me with any tech notes or verification of said damages/repairs 'requesting your assistance in determining if problems exist with the flawed service of Mercedes Benz of tucson or of a much larger issue with flaws in the manufacturing of 2012 E350 engine. 'at this point, I am not confident that the vehicle is safe to drive

- Oro Valley, AZ, USA

problem #7

Mar 032019

E350

  • 61,781 miles
Fan fire. Oil smelling smoke which turned to flames.

- Las Vegas, NV, USA

problem #6

Mar 012017

E350

  • miles
Engine. Problem started in March 2017. 2012 E350 conv made a loud grinding metal on metal noise on cold start, but would fade out in a few seconds. Brought car to dealer, who said mechanics could not duplicate problem. Brought car home and car continued to make grinding noise. Took video of noise on cold start so I could show my service advisor. Mercedes said to replace engine tensioners, total cost of repair $1900. Brought car home. Car continues to make grinding sound on cold start. Brought car back. Mechanics suggested changing the oil pump, total cost $570. Brought car home, and car continued to make grinding noise on cold start. Brought car back to dealer for the third time, who then called Mercedes for advice. Service advisor said Mercedes thinks that the car has a camshaft problem and the cost of parts alone would be over $5000. My car was in the shop for over 2 months and there was still no definitive answer as to what was causing the grinding metal on metal noise. This is absurd as I have had my car serviced regularly and it is garaged in great condition. This is obviously an engineering/mechanical defect and should be considered a lemon since Mercedes has not been able to fix or diagnose the problem in a timely manner. As of today, Feb 17, 2019, my car is still making a grinding metal on metal noise on both cold and warm start. Just wondering if one day my engine will suddenly blow up on cold start...

- Huntington Beach, CA, USA

problem #5

Jul 262017

E350

  • 115,000 miles

A D V E R T I S E M E N T S

2012 E350 coupe. Car was making an odd "clunking" noise when started, but would fade or idle out after a couple of seconds. Took it into mb service today and was just informed that my car has a camshaft problem and it's wearing on the right cylinder head. Service rep says they have seen several cars come in with the same issue. Repairs cost $9,000! seems like an engineering/mechanical defect as I was told there was nothing I could have done to prevent this issue.

- Nolensville, TN, USA

problem #4

Jan 082016

E350

  • 55,400 miles
When starting the vehicle has a slow start. When in motion the vehicle drives rough, and cuts off, then the check engine light came on. This vehicle has a great maintenance record only serviced at the Mercedes dealer and has 0nly 54000 miles. This is clearly an engineering issue which was a safety issue. Mercedes repaired. They found the camshaft damaged, head damaged, and gear damaged and replaced camshaft and gear only. They charged my for their engineering failures $4874.38. For this engineering and safety faikure I believe this vehicle should be recalled before the lost health and life is lost, and owners should be recompense for the damage.

- Hoover, AL, USA

problem #3

Nov 102014

E350

  • 19,990 miles
Ticking/ tapping noise from the engine bay when car is excelerating, especially when going uphill.

- Portola Hills, CA, USA

problem #2

Aug 142014

E350

  • 5,597 miles
The contact owns a 2012 Mercedes Benz E350. While the vehicle was parked and the key was removed from the ignition, the vehicle jerked and rolled backwards before stopping independently. In addition, the contact heard an abnormal noise and the vehicle veered to the left when reversing. The dealer was unable to diagnose the failure but made the following repairs: The cover on the front passenger side cylinder head, removed/installed a seal, non-return valve, chain tensioner, sealant mb, flange gasket, hexalobular bolt, the cover on the front driver side cylinder head, removed/installed a seal, left and right secondary drive chain tensioners, front cover cylinder, and the check valve. On another occasion, the vehicle rolled in reverse and crashed into the bumper of another vehicle. The door of the vehicle bruised the contact and medical attention was required. The vehicle was towed to the dealer. A police report was not filed. The dealer was not able to diagnose the failure and the vehicle remained at the dealer. The manufacturer was notified of the failure. The approximate failure mileage was 5,597.

- Sarasota , FL, USA

problem #1

Mar 182014

E350 6-cyl

  • 20,000 miles
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. If this is true then they actually in my opinion while developing safety features created another un safe condition where as the semi could have run over my wife and I killing us both. This was truly a near miss and we are very much concerned about it happening again to us or some one else, resulting in a fatal accident, not just a fender bender. Mercedes is in denial concerning any un safe condition and refused to take any responsibility for any damage that this car caused. Please review this vehicle for possible call back before some one does get seriously injured. Perhaps skid mode or traction control may be helpful but engine cut back and power loss needs to be left to the operator not the vehicle controlling it's self. Your help would be graciously appreciated.

- Chico, TX, USA

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