Mileage & vibration while idle

[AmirMann]

I own W212 E220 SE CDI BLUEEFFICIENCY S/S A from last about 2 years and the mileage in town is always around anything from 14.1 to 19mpg and 46-48 mpg on motorway long runs. Is this normal to have that low mileage in town as I had Mondeo before which gave me about 40-45 mpg in town. The car is Serviced about each 6-7 months.

secondly there is some kind of vibration when idle sometimes it comes something it is not there. The speedo also jumps sometimes from .9 to 1, so do not know what it is. Any help will be appreciated before i take it to local garage. I am in Manchester. Garage told me most likely it is Mounts but they are also not sure.

thanks in advance

amir

 

[mattkh]

.......The speedo also jumps sometimes from .9 to 1,

Do you mean the rev counter..?

 

[AmirMann]

Yes I mean rev counter. Sorry

its 2012 62 plate with 100k now

thanks for asking.

 

[mioba]

could also be a MAF, could be a vac leak. needs the codes read. You got a good MB indy to go to.

 

[mattkh]

Vibration while idling can be the diesel not burning properly which may be due to the injectors, and that would explain the high fuel combustion.

 

[AmirMann]

Yes i arranged for someone with a Star diagnostics next week

 

[AmirMann]

Why is the fuel consumption ok when at motorways? Its a bit confusing.
thanks for reply and suggestions

 

[AmirMann]

I have a icarsoft and last time I checked it showed

p208028 dont know what that is, but something to do with exhaust gas temperature

9ED149 humidity/temperature sensor malfunction

regards

 

[mioba]

thats your exhaust gas temp sensor. You car may be overfuelling to keep the temperature in acceptable ranges within the converter due to a faulty sensor. that said car needs proper diagnosis.

scanner are only as good as the user and many dont pinpont issues (bar xentry star).

if you dont know what your doing then leave to a garage or you will just be chucking money away.

 

[mattkh]

Why is the fuel consumption ok when at motorways? Its a bit confusing.
thanks for reply and suggestions

Say you have a leaking injector. You travel 5 miles in City traffic in 30 minutes.
On the motorway with the same leaky injector you have covered 60 miles in 30 minutes, so consumption looks better.

 

[AmirMann]

That makes sense, Thanks for clearing it up, Really appreciated. Have a great night.
Cheers

 

[AmirMann]

can someone help me with any reliable Mercedes repair shop near Manchester who can do diagnostics too.
The one I was booked with closed his shop for 3 weeks due to covid.

regards

 

[mattkh]

I have a icarsoft and last time I checked it showed
p208028 dont know what that is, but something to do with exhaust gas temperature

This is a temperature sensor that you can try changing.

 

[AmirMann]

Thanks for reply! Any how to do info? Part number or any help will be greatly appreciated.

I have car booked for diagnostics on 24th with Dronsfield in Royton.


regards

 

[mattkh]

Part number or any help will be greatly appreciated.

When you used your icarsoft, what did it show your engine code as. I need that.

 

[mioba]

Go to your local merc dealer parts dept with your reg and vin and get the part.

 

[AmirMann]

When you used your icarsoft, what did it show your engine code as. I need that.

Engine code: OM651.924

is this the one you are referring to?
Thanks

 

[mattkh]

The temperature sensor in the exhaust manifold is A 000 905 06 00 replaced by A 099 905 37 00.
If you can, I would like to see the screen of your icarsoft showing the exact details of the error code.
Thanks

 

[AmirMann]

Thanks for providing me with the part number.

i have attached the two screenshots of the error icarsoft is showing.

regards

 

[mattkh]

Thank you so much.
The P2080 screen I was hoping to give some more info. Anyway, my research agrees with yours. It is to do with exhaust temperature.
See if you can locate the sensor on the exhaust manifold. Apparently, it looks on the outside a bit similar to the O2 sensors one sees on the catalytic converters.