2014 Mercedes-Benz E350 Problems

What owners report

Owners of the 2014 E350 most often write about a gasoline smell around a parked car, brakes that fade or feel soft after brake lines corrode, and the loss of power steering assist while driving. A separate cluster of complaints describes rear speakers crackling, smoking and smelling of burning, and a fair number involve rusted rear subframes found during routine service, usually on higher-mileage cars.

1. 1
   Fuel system

   Gasoline odor or fuel leak around the tank

   • 34 complaints (12%)
   • median 78,000 mi at 10.8 yrs old (15 state mileage)
   • 2 mention a crash, fire or injury
   • filed 2014–2026

   Owners describe a strong gasoline smell inside or around the car, most noticeable after parking in a garage or after filling the tank past a certain level. Some report fuel visibly leaking near the tank area or the access under the rear seat, while others see no drip at all. Dealers and independent shops variously reported a leaking fuel tank, tank access area or lines; in some cases the smell could not be reproduced. Several owners cite recall 15V792000 by campaign number, and some say their VIN was not included. Reported from very low mileage up to roughly 150,000 miles, with many complaints filed between 40,000 and 90,000 miles while parked or just after refueling.

   Recall 15V7920001 related service bulletin

   What to check: Ask whether the fuel tank and feed line work under recall 15V792000 was done for this VIN. After a test drive, park the car and smell around the rear wheel arch and under the rear seat for fuel; check for any drip under the tank.

   2 excerpts from owner complaints in NHTSA records

   “When I put gas in the car beyond one quarter of a tank, I get a very strong gas smell coming from the drivers side rear fender and tire area.. There is no visible gas leak on my garage floor. The car is stationary/parked in the garage”

   NHTSA complaint #11399266, filed 2021-03, 70,000 miles

   “I bought my first mercedes 20 days ago, I was driving with my kids around 6:30pm when suddenly I smell fuel inside the car and another vehicle approaches me to advised me that my car was leaking fuel all over the road. I took my kids out of the car immediately and I contacted the mercedes benz service department for help and I was told by a receptionist that the service department was closed that I need to contact a tow service that way the vehicle can be deliver to the dealership for service. …”

   NHTSA complaint #10632357, filed 2014-09, 288 miles
2. 2
   Electrical system

   Crackling, smoking rear speakers and amplifier

   • 21 complaints (8%)
   • median 57,750 mi at 6.0 yrs old (13 state mileage)
   • 10 mention a crash, fire or injury
   • filed 2018–2025

   Complaints describe popping or crackling from the rear speakers, a burning smell, and in several cases smoke coming from the rear deck area; the noise sometimes continued after the engine and radio were shut off. Owners report the amplifier and speakers were found burnt or melted, with amplifiers, speakers and in one case a head unit replaced. Some owners say the dealer declined coverage and pointed to a faulty amplifier. Typically reported between about 45,000 and 70,000 miles, often after long drives or in hot weather.

   What to check: Turn the radio on and listen at the rear shelf for crackling or popping, and smell for hot plastic after a longer drive. Ask whether the amplifier or rear speakers have been replaced.

   2 excerpts from owner complaints in NHTSA records

   “While driving on the highway there was a burning smell coming from inside the car. My son pulled over and opened the driver side door there was smoke coming from the front door speaker. We found several complaints online of the same issue with same year make and model of mercedes. We brought it to ray catena in edison nj explained the problem and they stated it was not covered even though they stated a faulty amplifier after trying to replace the speaker which melted on them as well. …”

   NHTSA complaint #11354892, filed 2020-09, 67,300 miles

   “I was driving the car down 880 until I suddenly heard a cracklings noise coming from the back of my car. I had just gotten the car serviced a week before so this was very unpleasant and surprising. I ended up turning back and parking my car at home. The next day while driving to the dealer I still heard the noise and there was a weird burning smell. The noise continued even after shutting off the car. I went to the dealer and they diagnosed that the right passenger speaker had melted and they also changed my amp. …”

   NHTSA complaint #11331863, filed 2020-06, 67,000 miles
3. 3
   Suspension

   Rusted rear subframe and detached control arm

   • 76 complaints (27%)
   • median 72,000 mi at 9.2 yrs old (13 state mileage)
   • 3 mention a crash, fire or injury
   • owner-quoted repair $4,000 (median of 13 quotes)
   • filed 2017–2026

   Owners report the rear subframe rusting at the control arm area, found during routine service or after the rear of the car started to feel loose or shift under braking. In one case a rear control arm was reported to have detached from the subframe, and owners describe subframe and control arm replacement. Some owners mention an extended warranty on the frame rust but say their VIN was not covered. Mostly reported from about 59,000 miles upward, concentrated on cars in the 70,000 to 120,000 mile range.

   2 related service bulletins

   What to check: Have the car put on a lift and inspect the rear subframe and control arm mounts for corrosion, especially on a car from a wet or road-salt region. Ask whether the subframe has been replaced or repaired.

   2 excerpts from owner complaints in NHTSA records

   “Have purchased a 2014 mercedes E350 59k miles. This vehicle has an issue as so do many Mercedes with their rear subframes rotted out at the control arm bracket which causes the rear link/thrust arm to detach from the subframe/axle carrier and posses a danger when breaking due to the rear spindle assembly flexing throwing the wheels out of alignment and could be at risk for a car crack. This vehicle has already been in a minor crash as a result of this issue. …”

   NHTSA complaint #11472559, filed 2022-07, 59,000 miles

   “Brake line to rear completely rusted through. Lost brake control while driving. Upon further inspection, the entire rear subframe has significant rust damage that warrants replacement.”

   NHTSA complaint #11495481, filed 2022-11, 84,000 miles
4. 4
   Steering

   Power steering assist cuts out

   • 22 complaints (8%)
   • median 50,000 mi at 6.6 yrs old (11 state mileage)
   • 1 mention a crash, fire or injury
   • filed 2017–2026

   Owners report a power steering warning on the dash followed by the wheel becoming very hard to turn, sometimes at low speed in a neighborhood and sometimes while driving. One complaint notes the vehicle had to be stopped where it was; others had the car diagnosed with a failed steering rack, a steering control module, or a module affected by corrosion at rear sensors. Repairs described include replacing the rack or control module. Mostly reported between about 30,000 and 90,000 miles, occurring without warning during normal driving.

   Recall 16V899000

   What to check: Confirm whether recall 16V899000 for the electric power steering system was completed. During a test drive, watch for a steering malfunction message and check that assist feels consistent at parking speeds.

   2 excerpts from owner complaints in NHTSA records

   “'steering wheel malfunction' display while driving. The steering wheel couldn't be turned. I could either go straight or reverse, but could not turn the steering wheel. I was driving out of my neighborhood, all of the sudden, the display popped up, before I was going down the curvy hill. This is dangerous that it can just happen while you drive. It can take someone's life if drive out on the freeway at a high speed and the steering wheel cannot be turned. …”

   NHTSA complaint #11324969, filed 2020-05, 1 miles

   “While driving the onboard computer failed resulting in all the warning lights going on and disabling the power steering. My mechanic determined that it was due to the blind spot sensors which are located in the rear bumper going bad because of salt corrosion. Wrote to mercedes but have not received even a response. See the attached letter in the documentation section.”

   NHTSA complaint #11317743, filed 2020-03, 68,000 miles
5. 5
   Brakes

   Rusted brake lines and soft brake pedal

   • 41 complaints (15%)
   • median 64,609 mi at 9.3 yrs old (6 state mileage, few)
   • 1 mention a crash, fire or injury
   • owner-quoted repair $3,800 (median of 6 quotes)
   • filed 2017–2026

   Owners describe the brake pedal going to the floor or feeling spongy, with low brake fluid warnings, and in some cases the car taking longer to stop. Shops found the metal brake lines, particularly at the rear, rusted through and leaking, and replaced them. Other owners mention rusted rotors causing pulsation after the car sat for weeks in winter, which some dealers treated as normal wear. Reported from about 60,000 to 130,000 miles, often noticed in cold or wet climates and after the car sat unused.

   2 related service bulletins

   What to check: Have a shop inspect the rear brake lines for rust and check for brake fluid seepage, and test that the pedal stays firm under steady pressure. Ask whether the lines or rotors have been replaced.

   2 excerpts from owner complaints in NHTSA records

   “The contact owns a 2014 Mercedes-Benz E350. The contact stated that the vehicle was taken to an independent mechanic who informed the contact that the brake lines were extremely rusted. The contact related the failure to NHTSA Action Number: DP20004. The vehicle was taken to the dealer; however, the vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 126,000.”

   NHTSA complaint #11515448, filed 2023-04, 126,000 miles

   “The contact owns a 2014 Mercedes-Benz E350. The contact stated that the brake pedal was spongy while depressed, with the Brake System and Low Brake Fluid warning lights displayed. The vehicle was taken to a dealer, and the brake fluid was topped off; however, the failure reoccurred in less than 24 hours, and the same warning lights were displayed on the instrument panel. The vehicle was taken back to the dealer, and the technician was informed that there appeared to be a brake leak. …”

   NHTSA complaint #11764083, filed 2026-09, 67,218 miles

Buying note. A pre-purchase inspection on a lift is worth the cost on this model year: have a shop look at the rear subframe and brake lines for corrosion. Also confirm which of the open recalls for this VIN, particularly the steering and fuel line campaigns, have actually been completed.

Summary written with AI from a sample of 60 NHTSA complaints for this model year (picked at random, with complaints that state a mileage and recent ones taken first), then checked automatically against the source records. Where a problem shows a complaint count, every complaint for this model year was matched with fixed keyword rules (written with AI and tested against the sample), and the mileage, age and repair figures are calculated from those complaints; owners' figures are as stated, not verified. Other counts refer to the sample. The excerpts come from NHTSA's public complaint records and are unverified; capitalisation is normalised, NHTSA staff notes are removed, and shortened text ends with “…”. Something wrong? Request a correction.