Keith66

Between the wrist pin issue and #1 piston cracking issues with the M274 engine (2.0 4 cyl gas), my level of confidence in the longevity of this engine is low.

So I'm wondering how many of you are considering selling or trading in your W205/M274 (or already have) based on these engine issues?

Myself, I'm close to that point. I love my C300 and have poured a lot of blood, sweat and tears (and a large pile of money) into my car, but I find myself constantly concerned that today is the day my #1 decides it doesn't want to play anymore.

I'm currently at 51K miles and it has been a great car so far. However, I'm becoming weary of worrying about how much time me and the engine remain friends.

I'm planning a ~3000 mile road trip in the coming months and I'm considering renting a car for it and that's just not right. I should be able to trust my car, but I really don't… unfortunately.

So how many of y'all find yourself in my position?

E55Greasemonkey

AAA plus and a powertrain warranty. Then keep it.

Cosworth2000

I love my V6 Turbo and it is a strong engine.. I'm so sorry for those that purchased the C300 and having these problem.

Keith66

AAA is great advice and I have it.

I wish a warranty was a solution, but to me it isn't. I've jumped off the extended warranty train as they are all experts at finding obscure ways to weasel out of coverage. In the past 10 years I've spent over 7K on extended warranties and have received around $400 in benefits and have paid around $3K out of pocket. It's a frustrating and stressful battle. I'm sure if my engine explodes, it would be something like "since your windshield washer fluid was only half full, we're sorry to say your engine is not covered, this is clearly defined on page 112, paragraph 8, item 5b."

To me, this just adds more stress to the situation. I'm with you though, I wish that was the answer.

Keith66

Thanks man. I'm sorry about it too (for myself and all others potentially affected).

Yeah, I've been eyeballing models with the M276 engine.

Adi-Benz

That's why I'm not letting any of my family members get any of the 4cyl Mercedes models. Just too many reports. Frankly if you want a 4 cylinder a lot of the brands have stepped up their interior quality with the newest models.

Especially since you have a '15 its relatively high risk. But of course, there is more that are fine than are problematic. But an m276 vehicle upgrade could be well worth it.

Keith66

Agreed. I mean, chances are I can get 100K+ miles with no engine failures but it has also become a psychological thing and has eroded my confidence.

E55Greasemonkey

What year is your car?

Keith66

March 2015.

Keith66

Actually, June 2015, just re-checked my VIN printout.

Keith66

And looking at it again, that was the delivery date. Not sure of the engine production date.

E55Greasemonkey

Thanks, now I can see that on your profile using my PC (mobile app doesn't show that.) Obviously that's the worst year, all I can suggest is make sure to always run premium gas and don't put a tune on it. I've seen failures from both these situations.

Keith66

Thanks for the insight dude. The car has had 93 octane (always) since I bought it in 2018. I do have an ECM flash tune and I think it's time to load back my stock tune while I make a final decision of what I'm gonna do.

I know I'm going to sell it/trade it in, just not sure yet if I want to do it right now or wait a number of months.

I planned to keep my C300 for a good while, but as I said earlier, I'm tired of worrying about this so it's time to fix that.

E55Greasemonkey

A coworker had a piggyback on his low miles '17 or '18 (don't remember) and chipped a piston. It was the only newer model c300 that I've seen a chipped piston on....

Keith66

Ouch, that's no fun. I've been running my tune for about 2 years and I now have a feeling like my luck may be running out, lol.

cidtek

Could a mechanic who is really good at using a stethoscope tell if the wristpin is causing any noise due to slop in the fit? It seems that owners of cars that are grenade prone have reported a noisy rattle in the cylinder.

Keith66

Good thinking and I think you're right. I think the key to that is to have a trained ear to know what to specifically listen for and most likely those people can be found at MB service departments.

For me at least, that's the last place my car will be since they massively and unjustifiably overcharge for everything, unfortunately.

Holmes5518

I recommend the C450 to everyone. It is a bargain for what you get.

Cosworth2000

I wonder if anyone with a CLA45 has engine problems with their hand built engines?

MaverickC43

Damn man. You have put so much into this car!!
I clearly don’t know much, but it would be nice if you could do work on the engine to increase longevity & durability 🤷🏻‍♂️😩

Keith66

I don't know, but I would think a 2.0 built for 400+ horsepower would have a forged crank, rods and pistons.

MaverickC43

100% better.
or I think we’d hear about the carnage

Keith66

Yeah dude, that's why I'm so torn. I love the car and I don't think I want to add up all the receipts, cause I don't feel like crying, lol. But I'm easily at $15K worth of mods.

I could go down the engine build-up rabbit hole, but myself, I can't justify that for a 4cyl. Not worth it to me.

Still not sure what I'm going to do at this point.

Keith66

There are some deals to be had out there.

http://atcm.co/VDPTXTSHRE/280c16a2

W205C43PFL

Really hate to see you dumping all that mod you put in, your car is truly unique and very personally yours, hopefully you still have the stock parts to put on and so you can put these mods in a C 400 or C 450 or even one of those C 43
Good luck on the search of the vehicle, looking forward to hearing more.