I purchased my "Certified Used Vehicle" from a dealership that is now no longer in business. It had 20,000 miles on it when I purchased it - it was 2 years old. I've maintained it through a certified mechanic and not at the dealership because the dealership financially rapes you the minute you walk in the door. I know, since this is my 4th Mercedes. I was driving the car with no issues and suddenly on the freeway, the car started to shudder, black smoke billowing out the back. Pulled over immediately and brought it to my mechanic. Number 1 piston is blown - needs a new engine.

The car has been maintained and only has 65,000 miles on it. I purchased the car for $30,000 and now it is worth nothing! The dealership says it will be over $10,000 to fix the problem, but now reading other people's stories on here, I realize that chances are it will happen again with these motors. Mercedes needs to step up and assist people with a problem that is clearly an issue with their/this motor. If they screw me I will never own another Mercedes.

I was driving my Mercedes on freeway when it slowed down abruptly causing huge traffic issues and several close calls on accidents. There was burning oil and smoke. The check engine light went on. It was quite a huge panic situation at 70 miles per hour. I pulled over and the car was only able to go about 13 miles per hour at that point. I called Mercedes after I got trouble codes that basically said there’s been a fatal error. It said not to drive it. I had it towed to Mercedes, Fletcher Jones of Newport Beach.

They denied ever hearing about such a problem but then diagnosed it as a cylinder 1 crack without doing a compression test and while driving it around the shop after I asked them not to. They knew full well what was up and told me it would be $21,000 for a car I bought with manufactures warranty still on it and had put about 9,000 miles on.

When I researched the issue I found hundreds of C300 with M274 engines had complaints of the exact issue I was facing. I found that Mercedes knew about my problem years before they sold me this car. I took Fletcher Jones motor cars to small claims court because I signed a horrible contract with them that does not allow me to do anything else. I presented many cases of engine failure just like mine due to wrist pins. I told the court I purchased it with warranties left on it. I showed clearly that there were Mercedes to Mercedes memos on the recall years ago. I showed internal memos of the eventual ignoring of the recall. I showed internal memos that Fletcher Jones received from Mercedes telling them exactly what I was saying and took me months to dig up. They have known the C300 was defective for years and they lied directly to me and the court and I lost the case. This car has ruined my credit and threatens to do more damage. Mercedes has 4 models with this engine wrist pin issue on it. They are liars and cheats and I can’t wait till they are finally found out.

It looks like we may get some help with the new complaint being considered. Please file any complaints on your c300. It will fail and they will lie. We all need to work together. I can’t believe that the upstanding reputation that Fletcher Jones motor cars of Newport Beach & Mercedes Benz have shared for years is just a fantasy.

My car is 2016 Benz c300 with 50k miles. First car was firstly shaking at idle, then check engine lights on after couple days and dealership remove the code by replacing the fuel injector, but the engine was still shaking unusually. I returned the car to the dealership and they told me the one piston was cracked, but since fortunately I bought extend warranty years ago, they fixed the car with replacing piston, spark plug etc.

I was lucky that I do not have to pay anything because of my extended warranty, but this engine is so unreliable that there are a lot of cases with this similar issue, which is piston cracked at around 50000 miles.