Mercedes Benz C250 engine problems

ENGINE

my car overheats badly and shakes and it is starting to smoke from the hood in snowy conditions

NHTSA complaint #11716648 — an unverified report by a vehicle owner.

ENGINE

The vehicle was represented to me as safe to drive, with no major mechanical issues, and that it would pass emissions after only a simple minor fix. After I took possession, the check engine light came on. The car began running rough and showing hesitation. A scan immediately showed a camshaft position sensor fault, cylinder misfire, lean fuel condition, and oxygen sensor/emissions faults. I was also told by a professional shop that the timing chain may be failing. I was then warned that these problems can cause power loss or engine stalling while driving, and that the vehicle in this condition would likely not pass a legal emissions inspection. I was never told about any of these safety or emissions problems before taking the vehicle. This situation creates a safety risk because sudden loss of engine power or stalling can happen in traffic.

NHTSA complaint #11697039 — an unverified report by a vehicle owner.

ENGINE

I was coming off the freeway on 9/25/25, and when I pressed on the breaks they completely locked up and would not break at all. The car turned off, no warning lights nothing, and I continued to hit the break and the car would not stop, then all of a sudden it came to a stop almost colliding within inches of hitting the Semi-Truck in front of me. This is the second time in one year that this has happened to me, I have had the car checked out the first time last year immediately, and even paid to diagnose it, nothing, I had the brakes and rotors replaced last June of 2024 when this happened. Since then the car has only been in the dealership to get the car Fully checked out mutltiple times within 2024, 2025 and repaired by Mercedes dealership. On 9/25/25 this happened to me and it was a traumatic experiance when I pressed the break and the break got super hard and in a Locked position and would not come to a stop, there was no warning lights, no engine lights, nothing. (increased braking effort, and potentially I was inches of collision risk. I had the car towed to the nearest shop and was told this is a collapsed break booster Vacuum pump, and possibly the hose and lines and possibly further problems but they would need to replace the Vacuum pump first. After I looked to see if there was a recall on the vacuum pumps in that model on google and it says the following; Google- 2014 Mercedes c250 recall on Vacuum pump A-Premium Vacuum Pump Compatible With Select Mercedes ...Yes, there was a recall on certain Mercedes-Benz vehicles, including some 2014 C250 models, related to a defective brake booster vacuum hose. The recall involves hoses that may delaminate over time, leading to a loss of vacuum, increased braking effort, and potentially a collision risk. To check if your specific 2014 C250 is affected by this recall, you should contact an authorized Mercedes-Benz dealer or visit the Mercedes-Benz USA website to check for open recalls for your vehicle's VIN.

NHTSA complaint #11690125 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2012 Mercedes-Benz C250. The contact stated that while driving at an undisclosed speed, there was an abnormal rattling sound coming from the vehicle with the check engine warning light illuminated. The contact drove the vehicle to the shoulder of the road. The contact stated that the rattling sound continued, and the vehicle shuddered abnormally. The vehicle was towed to the residence. The independent mechanic provided mobile service and diagnosed the vehicle with cam shaft timing chain adjuster failure. The contact was informed that the cam shaft timing chain adjuster needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure but provided no assistance. The contact was advised to contact the NHTSA Hotline and report the failure. The failure mileage was approximately 150,000.

NHTSA complaint #11681296 — an unverified report by a vehicle owner.

ENGINE

My Mercedes Benz 2014 W204 C250 initially had a noise during startup. The startup noise became louder and now my car does not start. Also, the check engine light indicate a cam shaft position sensor error. Looking online it appears that my problem is exactly like the problem described in a NHTSA report on 2012-2015 W204 and W172 vehicles(C250 and SLK250) equipped with the M271 engine. I would like NHTSA assistant in getting my Mercedes Benz W024 C250, VIN [XXX] included as part of extended recall of the same car and engine and repaired. If more information is needed, please contact me. [XXX] [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA complaint #11672484 — an unverified report by a vehicle owner.

ENGINE

The model/year Mercedes-Benz are well known for experiencing this/these particular issues. My research has shown that these year/make/model vehicles are experiencing the same type of mechanical failures nationwide. The issues all relatively begin around 75,000 miles. I've only had my car 3 years putting 30000 on it hardly driven/cared for **Issue Found:** Oil was leaking onto the ignition coil and spark plug of cylinder 3. **Source of Leak:** Valve cover gasket failure. **Recommended Repairs:** - Replace the valve cover gasket (to halt the oil leak). - Replace spark plugs and ignition coil (which were contaminated/damaged by oil). **Relevance to Warranty:** The valve cover gasket is only covered if it fails as a result of an internally lubricated engine part causing damage. Ignition coils and spark plugs are maintenance items and are not covered by warranty plans. **Required Repairs (Identified Mechanical Issues)** - **Coolant Pipe Leak – $850** **Issue:** Coolant leaking from a pipe on the side of the cylinder head. **Relevance to Warranty:** Typically not covered unless it pertains to a failure in a covered system such as the water pump or cylinder head due to an internal breakdown. This is likely classified as an external plumbing component, which is not included. - **Oil Feed Line Leak – $600** **Issue:** Oil leaking from the side of the engine, traced back to the oil feed line. **Relevance to Warranty:** This is not typically covered unless the oil feed line is part of the oil pump system and has failed due to an internal issue (usually regarded as an external line). **Other Items Found (Worsening Issues)** - **Timing Chain Rattle / Cam Adjuster Noise – $6,000** -**Issue:** Rattling sound during startup. **Diagnosis:** Noise emanating from the timing chain and camshaft adjusters. **Relevance to Warranty:** This is covered under Secure Plus, as both the timing chain and camshaft adjusters are recognized as internally lubricated par

NHTSA complaint #11666448 — an unverified report by a vehicle owner.

ENGINE

News Channel Update | Warranty Mercedes-Benz USA, LLC A Mercedes-Benz AG Company One Mercedes-Benz Drive Sandy Springs, GA 30328 770.705.0600 IMPORTANT EXTENDED WARRANTY INFORMATION Mercedes-Benz AG (“MBAG”), the manufacturer of Mercedes-Benz vehicles, has determined that on certain Model Year (“MY”) 2012-2015 Mercedes-Benz Model 204 and 172 vehicles (C250 and SLK250), the warranty on the camshaft adjuster will be extended from the original 4 years/50,000 miles to 10 years/120,000 miles (whichever occurs first) from the original warranty start date. This camshaft adjuster extended limited warranty applies to all conditions that necessitate the replacement of the camshaft adjuster under the standard warranty terms and conditions. The extended warranty is applicable to the following vehicles: Model Years Sales Designation Engine Type C-Class 2012-2014 C250 M271 C-Class 2012-2015 C250 Coupe M271 SLK-Class 2012-2015 SLK271 Please be advised that all camshaft adjusters being claimed under warranty must have a short test with fault code attached and will be inspected. All camshaft adjusters found to be functioning properly or without proper documentation will be returned and the claim debited in full. The following damage codes and parts kit can only be claimed for the replacement of the camshaft adjuster: Damage Code: 05050 – Camshaft adjustment, intake camshaft Damage Code: 05052 – Camshaft adjustment, exhaust camshaft Parts: A 271 050 21 00 80 – Camshaft adjuster, kit IMPORTANT: 1. Always check VMI to determine if a vehicle is covered under the 10 year/120,000 mile warranty period 2. Short Test Documentation with fault code information (P001477, P001600, P001762, P001662, P001177, P001700, P001192, P001492, P034062, P036662) must be attached to all returned camshaft adjusters Please check the VIN in Netstar/VMI before scheduling the appointment for the repair. Applicable vehicles will be visible in Netstar/VMI on October 30, 2020

NHTSA complaint #11658655 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2013 Mercedes-Benz C250. The contact stated while driving approximately 50 MPH, there was an abnormal knocking sound and a metal-on-metal grinding sound coming from the vehicle. The contact slowed down and stopped the vehicle. The contact restarted the vehicle and heard the same abnormal sounds coming from the vehicle. The contact stated that there was no warning light illuminated. The contact had the vehicle towed to a local dealer, where it was diagnosed and determined that the camshaft needed to be replaced. The vehicle was not repaired. The manufacturer was informed of the failure and referred the contact to the NHTSA Hotline for assistance. The failure mileage was approximately 75,000.

NHTSA complaint #11654546 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2012 Mercedes-Benz. The contact stated while driving at an undisclosed speed, the Check Engine and High Pressure Fuel Pump warning lights was illuminated. The failure occurred on several different occasions. The vehicle was taken back to the residence. The contact did research and was made aware of an unknown NHTSA Campaign Number however, the VIN was not included. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was unknown. 

NHTSA complaint #11652861 — an unverified report by a vehicle owner.

ENGINE

I was told this from a BENZ dealer. There was a warranty extension on this VIN: [XXX] that ended on 03/02/2023 which, had to do with adjustment units for the camshafts. Nothing we could assist with goodwill on this due to the age of vehicle. This is NOT fair and I’m experimenting this exact process and Mercedes Benz does not want to take responsibility and get this fixed for me. Now my vehicle can not pass a smog test required. Please help INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA complaint #11652445 — an unverified report by a vehicle owner.

ENGINE

1. The car radio, blue-tooth, speakers, sound, car remote sound. Happened after a battery change by AAA - unsure if it's related. CUstomer service tried to resolve it - radio turns on, but nothing else works. 2. Doors won't unlock outside or inside - except passenegers side is open. 3. Accelerator acting strange - won't pick speed after 30, then 60 4. there was an air bag recal of this car a while ago.

NHTSA complaint #11638695 — an unverified report by a vehicle owner.

ENGINE AND ENGINE COOLING

The contact owns a 2013 Mercedes-Benz C250. The contact stated while the independent mechanic was performing an oil change on the vehicle, the mechanic informed the contact of a coolant leak. The vehicle was not diagnosed of repaired. The dealer and the manufacturer were not notified of the failure. The failure mileage was unknown.

NHTSA complaint #11636131 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2013 Mercedes-Benz C250. The contact stated while driving at approximately 40 MPH, the vehicle shuddered and stalled. The failure occurred on several different occasions. The check engine warning light was intermittently illuminated. The vehicle was taken to a dealer however, the diagnosis was pending. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was approximately 60,000.

NHTSA complaint #11635286 — an unverified report by a vehicle owner.

ENGINE

MY VEHICLE, HAS THE ENGINE MAKING NOISE ,WHEN STARTING,, THE LIFTERS RATTLE...I WAS TOLD TO CHECK WITH MERCEDES BENZ FOR RECALL INFO...HOWEVER, THE COMPANY STATES,THIS VEHICLE IS NOT INCLUDED....IT HAS 52,000 ORIGINAL MILES, AND HAS BEEN MAINTAINED...I BELIEVE, THIS PROBLEM SHOULD BE COVERED BY THE MANUFACTURER...PLEASE ADVISE.....I HAVE HAD THE MB DEALER DO A DIAGNOSIS..THEY CONFIRM THE LIFTERS ARE DISFUNCTIONING....

NHTSA complaint #11629391 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2013 Mercedes-Benz C250. The contact stated while driving 25 MH, the check engine warning light illuminated. The vehicle was taken to an independent mechanic, where it was diagnosed that the camshaft adjuster had failed and needed to be replaced. The vehicle was being repaired. The dealer was notified of the failure. The manufacturer was notified of the failure and informed the contact that the vehicle was not covered under an Extended Warranty because the 10-year time frame had been exceeded. The failure mileage was approximately 94,328.

NHTSA complaint #11626398 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2013 Mercedes-Benz C250. The contact stated that while the vehicle was parked, there was an abnormal sound coming from the vehicle. The check engine warning light was intermittently illuminated. The contact was made aware of an unknown recall; however, the VIN was not included. The vehicle was taken to an independent mechanic where it was diagnosed that the cam shaft adjusters needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline to report the failure. The failure mileage was approximately 40,000.

NHTSA complaint #11626033 — an unverified report by a vehicle owner.

ENGINE

Driving on [XXX] to Atlanta GA my car would not automatically shift and began to vibrate badly. I was almost hit by other vehicles as I pulled off the highway to check car out. Car was vibrating badly in idle and when I resumed my trip back home the car would not accelerate properly and caused tremendous stress and danger. Figured out that car would not shift automatically and I was forced to shift the car manually. Car would sputter and vibrate badly and would only slightly less vibrate to where I could drive it home in gear D5 and would less vibrate at 75+ mph very dangerous, and would lose power and shake violently going up highway hills. I prayed all the way home and barely made it shaken. I called my Mercedes Benz Dealer from the highway and immediately scheduled appointment on 8/15/24. This was a major safety hazard and life threatening situation with my Mercedes Benz C250 2014 car. My car 100% serviced over the years at dealership I bought it from Rick Hendricks Mercedes Benz of Lake Norman NC. Thank you for your time! Actor & Model [XXX] [XXX] [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA complaint #11607584 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2013 Mercedes-Benz C250. The contact stated while starting the vehicle, there was an abnormal sound coming from the engine. The dealer was notified of the failure. The vehicle was not diagnosed or repaired. The contact related the failure to an unknown Extended Warranty Coverage. The manufacturer was notified of the failure and advised the contact there would be no assistance due to the mileage on the vehicle. The failure mileage was approximately 100,000.

NHTSA complaint #11606181 — an unverified report by a vehicle owner.

ENGINE

I was driving on the highway my car sort of hesitated for a brief second then continued on as if nothing about one mile later my car began to slow down while I was in traffic so asap I pulled over at this point I could only go about 40 miles per hour which was very terrifying at that time it came a complete stop. After restarting the car 3-4 times it stayed running I continue home which was about 12 miles from my current location. For the next few days I did not go any where. I then had an appointment to have the 80,000 mile maintenance I mentioned the problem I was then told I need a throttle body replacement costing more than $2000 that I can not afford. At that time I started researching my own problem. My relative who works on 18 wheel truck for a living, . that perhaps it just may need cleaning rather than replacement . Also per my research this happens quite often with this model it also stated that Mercedes C250 was the worst Mercedes of that year many many owners have had this problem. The yellow ESP light come on saying it is off also my hold brake no longer works. It work at my prior dealer appointment it while going to appointment afterwards it did not work since over 9 years seldom used I wasn't concerned thus that is the message that appears when car fails Mercedes wants me to pay I believe $2000 problem not needed

NHTSA complaint #11601521 — an unverified report by a vehicle owner.

ENGINE

What component or system failed or malfunctioned, and is it available for inspection upon request? As I started my car from a cold start and even when starting the engine, the car was creating this tractor like sound. No system has failed but I read the camshaft adjuster and tensioner pulley has come out of site, which can ruin the engine. Has the problem been reproduced or confirmed by a dealer or independent service center? Yes, it was audible by the dealer but I was told that it would be a normal issue on a cold start. Now they will charge $200 for a service diagnosis. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? Mercedes Benz gave an extended warranty on the program for extension of 10 years but the problem has been happening for multiple people and it has been happening again that this warrants a recall over a poorly designed part that can destroy the car’s engine. Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? No such codes or messages. Which is why this is so scary. This incident has been happening for the past 8 months or so and besides a letter about a warranty no such information.

NHTSA complaint #11588738 — an unverified report by a vehicle owner.