M276 Engine Advice, Please

[88H]

Hello everyone, I have owned a W211 E220 for the past 12 years which has served me well - it is now 17 years old with 180k miles and I am considering a change. I viewed a C218 CLS 350 V6 petrol yesterday and would hugely appreciate any advice as I am not mechanically minded. It is 14 years old with FMBSH and 57k miles. The area of concern I have is the advisory from the MOT February this year which states:

• Engine oil level on minimum
• Nearside Front Oil leak, but not excessive engine oil weep/engine has a light misting of oil (8.4.1 (a) (i))

I attach images from the vehicle and would be extremely grateful if anyone has any thoughts or can see any obvious areas of concern.

Many thanks

 

[E55BOF]

Engine oil level is not tested in an MoT test, so cannot be a test advisory as such. If the oil level was checked just after switching off a hot engine, the reading will be too low, because the oil has not had a chance to find its true level after switching off; it needs to be left for a few minutes to give an accurate reading.

Is this a private or dealer sale? When was the last service carried out? If it's a private sale in particular, and it is due a service soon, a possible reason for a low oil level would be that the oil level has dropped since the last service; some Mercedes engines do use a little oil between services.

It's not uncommon for engines to develop slight oil seeps. That doesn't look too bad at all, and it would not put me off.

 

[88H]

Many thanks E55BOF - your thoughts are greatly appreciated. It is being sold by a dealer and was last serviced in June last year so the next one is due next month. To be honest the car appears to be in remarkable condition. I appreciate that a car of this age will require some attention but am keen to avoid buying something that could be disastrous. Many thanks.

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[markjay]

There may have been a low oil level warming on the dash?

 

[fabes]

Had that engine in a 2012 E class Coupe.
Faultless (see below) fast and not bad on fuel over 4.5 years

Serviced on the dot, but did have the usual problem with the nox sensors,

A gearbox service and plugs will be due on that one unless done, so check those out

Let us know how you proceed....

 

[88H]

Many thanks, fabes - I noticed from the MOT history that the MIL had been on in the past and thought this might have been nox related and now know from seeing invoices the nox sensors have been done. Thanks for the heads up about gear box service and plugs. I have a trusted indie who I will entrust all this to but feel a bit daunted about the initial purchase of the car because of my lack of mechanical understanding.

 

[TC350]

I have the M276 engine in my C350 and can confirm that it’s a brilliant engine.

But, there’s always a but isn’t there, the NOx sensors are an issue. Or at least the software keeping an eye on them is an issue. It’s my belief that rather than them failing as indicated by checks on the car’s computer, they just go out of a nominal range occasionally.

My engine is roughly the same age and mileage as the one you’re considering, but the NOx sensors have been replaced three times. The last time was six years ago. Since then, when the EML has come on and my OBD2 reader says a NOx sensor has failed, I’ve simply cancelled the code. Then no more notification for a year or so.

Most of my mileage has been short journeys and I suspect that the sensors have just got gummed up a bit as a result. A good blast cleans them then all is fine.

There’s no such thing as a fault free engine in any car. Complete maintenance is the best way to reduce the likelihood of faults. The attached looks worrying, but these faults are rare. I haven’t encountered any of them in the 13 years I’ve had the car.

Common Issues of the Mercedes-Benz M276 Engine: A Comprehensive Guide

Introduction:Common Problems with Mercedes-Benz M276 V6 | 603 MTech Autowerks®Mercedes-Benz is renowned for producing luxury vehicles with high-performance engines, and the M276 engine is no exception. However, like any complex machinery, the M276 engine may encounter certain issues over time...

www.603mtech.com

 

[Fastcar155]

I had the M276 turbo and apart from replacing two NOx sensors.

My car had done 43000 miles over 7 years and had a full MBSH.

I changed the engine oil rather a lot but that's me.

I ran the car on 99 octane petrol.

Superb engine and economical.

 

[fabes]

After having the M276 in the E350 coupe, I swapped it for the same engine in my current 2016 E400 coupe (with added turbos though)

Just done 3 completely fault free years in it, mixing long and short journeys.

Prior owner had had both nox sensors replaced, but I am told the later batch of replacement sensors aren't made of chocolate and are, now actually reliable.....

Do do the plugs and the ATF though, if due

 

[88H]

Many thanks to everyone for their thoughts which are greatly appreciated. I picked her up this morning and drove home 100 miles and all seems fine so far…

 

[fabes]

Very, very nice

Hope you get the same experience (and luck) I had with that engine.

Do you have shopping list of "bits n bobs" that you want to look at on it?

 

[88H]

Many thanks - the rear seats appear never to have been sat on and the boot never used so quite remarkable condition really. Booked in next week with my Indy so only then will I start to have an idea of what’s needed….