2011 W212 E250 - sudden late upshifting and check engine light now on

[derektrotter]

Hi All

I've got a 2011 W212 E250 with the 7g plus transmission, full Mercedes history so serviced as per schedule etc.

While driving home yesterday I noticed that my engine was revving much higher then usual before upshifting, it was revving to 2.5k or a bit higher before shifting in eco mode, it was like this all the way home, about 40min journey.

Today morning I thought i'd take it on the motorway, everything was fine for the first 10 mins, shifts were back to normal etc, but then it started doing the same thing when I hit about 70mph and now i've also got a yellow/orange check engine light on.

Has anyone ever seen this before? first fault i've had on the car and am a bit concerned, I should have Mobilo, if I call them would I get a free diagnostics? if not tempted just to take it to a indy to plug into STAR, theres no noises, when it does shift its smooth etc.

Advice appreciated

 

[ph47mf]

been driving in city a lot lately? possibly a regen?

 

[st13phil]

Assuming it’s the 250 diesel, then when the DPF regen’s the upshift engine speed is increased but I would have thought you’d be familiar with that.

If you have Mobilo then they will come out and run diagnostics on the car for you, but I suspect that they would then want to ship the car off to a main dealer if it can’t be fixed at the roadside.


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[derektrotter]

Yep its the diesel, I've never had this before so wasnt sure if it was the regen, regen would not trigger the check engine light would it?

I drive for 40mins at a constant 60mph once a week on the motorway so thought that would be sufficient for the DPF, also had a 30min motorway journey today morning, is it still safe to drive? theres no other scary warnings, just the yellow/orangeish engine symbol.

 

[st13phil]

A DPF Regen won't cause the EML to illuminate, so I'd say there's a fault somewhere that should be diagnosed.

 

[ph47mf]

yellow engine light doesn't point to a serious problem, so I'd say it's still safe to drive.

wait till after 3 drive cycles, it may go off on its own, if not time to plug it in.

 

[derektrotter]

Many thanks for the replies, light didn't go so I called Mobilo as per suggestion here, they came out and there were 2 faults:
1) P023714 - the boost pressure sensor has a short circuit to ground - this is what had triggered the EML.
2) "mil off. manifold flap dtcs also present" - it was relating to manifold actuating flap, he said this one may be being caused by the faulty sensor above however so he said first point of call was to replace the sensor.

He replaced the boost pressure sensor, fault light has gone away but it still seems to be holding onto the gears a bit but not as bad as before, e.g. normally it would upshift by 2k rpm, I was at 2.3 and it was still climbing, however only had time for a short drive as he had other jobs waiting, he said the manifold actuating flap fault has not returned anymore so give it a few drive cycles and see if the upshift pattern returns to normal, if not sorting the flaps is expensive apparently, are there any known issues similar to this on the OM651 CDI?

Driving home is 35min so will see how that goes.

 

[philt32]

Can i ask, what’s Mobilo?


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[derektrotter]

engine light is back, same symptoms, wonder if I even needed the sensor or a waste of money, time to to take it in I think.

Mobilo is MB’s breakdown cover.

 

[philt32]

How embarrassing[emoji33] been driving a Mercedes for around 15 years and never realised, I thought it was just recovery [emoji35][emoji35]


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[philt32]

engine light is back, same symptoms, wonder if I even needed the sensor or a waste of money, time to to take it in I think.

Mobilo is MB’s breakdown cover.

Frustrating to say the least, surely if you take it to a MD they must take into account you’ve spent money on it not being cured using a Mercedes service, ie at the very minimum some discount on your costs so far if something else is faulty?


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[Kwallace]

engine light is back, same symptoms, wonder if I even needed the sensor or a waste of money, time to to take it in I think.

Mobilo is MB’s breakdown cover.

Can you tell me what the outcome was as my car is doing the same? X

 

[Eddy77]

Is it worth resetting the gearbox learning. There’s a simple procedure which resets it....google is your friend. I did my clk 7g box a year or two back and it did make a difference!

 

[TriKlops]

Hi derektrotter and Kwallace! Did you solve that late upshifting and engine light problem? If yes, can you tell what finally caused this