I purchased this vehicle in July 2020. I did a through check for recalls, warranty problems and could not identify any with this vehicle. From the get go the check engine light would come on. I checked the codes and they indicated an "electrical fault on bank 1, oxygen sensor 1. I replaced the wiring harness on that sensor as well as the sensor. From then until now the car would code weekly about the same issue. Eventually I started using a catalytic converter cleaner (it cleans off sulfur deposits) in an attempt to solve the issue. It would work for a couple of tanks of gas and then continuing coding. I asked MB on numerous occasions about what the issue was. They all said they had no idea. It looks to me like they knew what the issue was, but kept it to themselves. Several weeks ago I received a letter in the mail(not dated by postmark) but the letter was dated August, 2023. The letter outlined an issue with the catalytic converter system identifying my vehicle by vin. The same problem I have had all along. The letter came at a time when the car codes almost daily with the same issue as always, ONLY NOW THE VEHICLE STALLS occasionally while waiting at stop lights. I said great. I called to get an appointment to fix the issue only to be told that the fix window had passed. I told them that I just got the letter. They told me that the fix expired in December 2023. I called MB hotline at 1‑800‑367‑6372 to see what was up. They said they would get back to me in 3 days. It's been a week so I called again and they advised me they can't help. It's an issue for the 2011, 2012, 2013, and 2014 MB S550 W221. Why is this not a recall and why won't they fix it. It's an expensive repair. They sent me the letter and said it was expired 6 months before I received the letter. Can you help?
The worst 2012 Mercedes-Benz S550 problems
Ranked by number of owner complaints. Mileage and cost come from what owners wrote.
- Engine3
- Fuel system3
- Electrical1
- Steering1
Problems by type
Tap a problem to see which part fails, at what mileage and in which other years.
- Engine3
- Fuel system3
- Electrical1
- Steering1
Recalls 2
Fuel system, gasoline
- What is wrong
- Mercedes-Benz is recalling certain model year 2011-2012 S400, S550, S550 4Matic, S63 AMG, C300, C300 4Matic, E350, GLK350, GLK350 4Matic, CL550 4Matic, and CL63 AMG vehicles manufactured from April 18, 2011, through July 12, 2011. Due to an irregularity stemming from the molding process of the fuel filter flange, the fuel filter flange may crack when operated in high temperatures.
- Risk
- If the fuel filter flange cracks, it will leak fuel which may lead to a fire if an external ignition source is present.
- Remedy
- Mercedes-Benz will notify owners, and dealers will replace the fuel filter, free of charge. The recall campaign is expected to begin in February 2013. Owners may contact Mercedes-Benz at 1‑800‑367‑6372.
Recall number 12V557000 · Recall details
Tires: pressure monitoring and regulating systems
- What is wrong
- Mercedes-Benz USA, LLC (Mercedes Benz) is recalling certain model year 2011-2012 S550, S550 CGI, S63, S600 Bi-Turbo, S65 AMG, S550 4-Matic, and S550 CGI 4-Matic and S400 Hybrid vehicles manufactured from March 3, 2011, through July 30, 2011, for failing to comply with the requirements of Federal Motor Vehicles Safety Standard (FMVSS) number 138, "Tire Pressure Monitoring System (TPMS)." The tire pressure monitoring system indicators may only illuminate for a portion of the time required by the standard and under certain conditions may not re-illuminate immediately after the vehicle is restarted as required.
- Risk
- If all four wheel sensors in the subject vehicles are simultaneously malfunctioning or missing, the TPMS will provide an initial warning, but this warning will not automatically repeat on subsequent ignition cycles, failing to remind the driver that the system is offline. Driving unknowingly with incorrectly inflated tires may result in sudden tire failure, increasing the risk of a crash.
- Remedy
- Mercedes Benz will notify owners, and dealers will reprogram the tire pressure monitoring unit, free of charge. The recall began on September 12, 2014. Owners may contact Mercedes Benz at 1‑800‑367‑6372.
Recall number 11V493000 · Recall details
Technical service bulletins for the 2012 Mercedes-Benz S550 80
Bulletins tell dealers how to fix known problems. A warranty extension means the manufacturer pays for that repair for longer.
- Engine
- Repeat workshop visit for vehicle vibration while braking from 60MPH. NOTE: Although the symptom is...
- Clanking noise from the area of the speakers in the doors
- Single throttle lift-off clunking noise from the side shaft when moving off (audible at the outboard end)
- After successful commissioning of the HERMES control unit (N112/9) with XENTRY Diagnosis DVD 03/2026, the...
- There are several types of complaint about noises or poor windshield wiper wiping performance: A: Wiper...
- Headlamp, front fog lamp leaky or fogged
- Headlamp, front fog lamp leaky or fogged
- Headlamps leaking or fogged
- Single throttle lift-off clunking noise from the side shaft when moving off (audible at the outboard end)
2012 Mercedes-Benz S550 fuel economy
Official EPA estimates in miles per gallon (MPGe for electric). Ranges cover trims that share the same engine.
| Engine | Drive | City | Highway | Combined |
|---|---|---|---|---|
| 4.7L 8‑cyl | RWD | 15 | 25 | 19 |
What 2012 Mercedes-Benz S550 owners say
Most recent owner complaints, unedited.
There is a strong smell of fuel in the cabin. When I lifted up the rear seats, where the odor is coming from, I see a film of fuel around the fuel sending unit on the driver's side. I lift up the sound insulation and I see fuel that has leaked on total the top of the sending unit.
Vehicle cut on fire while sitting lucky outside, the corner of engine passenger side bellow the headlight stores the suspension air pump and electric hydraulic steering pump.. Base on my inspection the ehps heated and set on fire.someone saw the car on fire and called fire dept.. Car was lock and store after hours
Tl* the contact owns a 2012 mercedes-benz s550. While the vehicle was stationary in a parking lot, the contact smelled fuel from the rear of the vehicle. There were no warning indicators illuminated. On september 5, 2019, the contact was alerted by someone of a fuel leak under the rear of the vehicle. Upon investigation, the contact associated the failure with the federal safety agency campaign number: 12v557000 (fuel system, gasoline). The contact called mercedes-benz of arrowhead (located at 9260 w bell rd, peoria, az 85382, (623) 815-3900) and notified them of the failure. The vehicle was not diagnosed or repaired. The manufacturer was notified of the failure. The failure mileage was 86,000.
There is an plastic plug in the oil system that leaks oil from the engine on to the exhaust manifold. This was reported because of increased oil consumption, vapor in the engine space and a smell of burned oil. The plastic plug is known to leak and mercedes does nothing about this during warranty and instead waits until the vehicular is out of warranty causing an increased time for a fire potential. This car is driven on city streets and highways with this fire potential.
Compare the 2012 Mercedes-Benz S550
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Questions about the 2012 Mercedes-Benz S550
Is the 2012 Mercedes-Benz S550 reliable?
Owners have filed 5 complaints about the 2012 Mercedes-Benz S550, fewer than a typical S550 model year.
What is the 2012 Mercedes-Benz S550 year score?
The 2012 Mercedes-Benz S550 scores 90 out of 100 (good). The score compares it with the other model years of the Mercedes-Benz S550: 75 is a typical year, 50 means twice the usual complaints, and serious complaints and recalls lower it.
What is the most common problem with the 2012 Mercedes-Benz S550?
Engine and cooling, with 3 complaints. Next is fuel system (3).
How many recalls does the 2012 Mercedes-Benz S550 have?
2 recalls, covering fuel system, gasoline and tires.
What gas mileage does the 2012 Mercedes-Benz S550 get?
Official estimates for the 2012 Mercedes-Benz S550 range from 19 mpg combined. The most efficient version (4.7L 8-cyl, RWD) gets 15 city and 25 highway.
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