Exhaust pressure sensor OM651

[sautah]

I’ve been chasing a weird issue where my 250cdi 2011 C207 has been changing gears that in my opinion was too soon. What I mean is it was overly keen to keep the revs low.

Eventually the car threw a P0471 error relating to the exhaust pressure sensor located near the rear of the egr valve.

Looking at the live data it seemed ok to my limited knowledge but as I can’t find anything else that could explain it ( I understand a split boost hose could trigger this somehow) I bit rhe bullet and have fitted a new one.
Part number for a new one is PMA0091535128

Now oddly the one that came out is nothing like this new part number so perhaps it’s either the wrong part fitted or just a very old part number

The car now appears to shift gears much smoother at a much more sensible time and doesnt hang onto gears / labour the engine like it was

 

[OneForTheRoad]

Where did you buy from ?

 

[sautah]

Mercedes Newcastle

 

[sautah]

Where did you buy from ?

Mercedes Newcastle

 

[OneForTheRoad]

Part number will be A0091535128. It's the latest version of the part available.

Your car will of been dropping into limp home mode with a faulty sensor , that's why the gears don't rev up. There's no turbo boost .

 

[Supernoodle]

If you looked at the live data before, did you make a recording and check the values after the change?

 

[sautah]

Part number will be A0091535128. It's the latest version of the part available.

Your car will have been dropping into limp home mode with a faulty sensor , that's why the gears don't rev up. There's no turbo boost .

Correct. That is the part I bought

 

[sautah]

If you looked at the live data before, did you make a recording and check the values after the change?

I did look at live data as mentioned above. The reading at idle on the old one was higher across the board from engine off to idle to 3000rpm where I decided to compare

 

[sautah]

After doing some decent miles today the whole car feels back to its normal heath. Power wise and gear change wise.