w210 e230 Flat acceleration and lumpy idle when starting from cold

[Djharps]

Hi Guys, I've got an issue with my Merc 1996 w210 e230 petrol.​

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When it starts up from cold the idle is lumpy until it warms up after a few minutes, then runs fine.​

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Acceleration is flat and slow, it has only been driven in town, but on Friday I gave it a good run on the motorway and now seems to be working beter, its more responsive.​

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Lastly the fuel economy isn't that great.​

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I also hooked up it up to a scan tool and obtained the following codes:​

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08/03/2015 17:01:06​

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035, Post
Lambda control is at rich stop : mixture too lean.​

Unmetered air, fuel injection valves, diaphragm pressure regulator.
!!! With TWC !!!
_____________________________________________________________
051, Post
Self-adaptation lower part throttle : too rich.​

Verify : unmetered air, fuel injection valves, diaphragm pressure
regulator, wear to motor.
!!! With TWC !!!
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I have been trying to work out what they mean, my guess is the first one is to replace Lambda sensor.​

The other one is to replace the MAF sensor.​

Has any body had experience of these code or symptom's?​

As I don't really want to replace anything I don't need to.​

Although since taking it on the motorway it has become more like it use to be, responsive.​

 

[Djharps]

I tried to clean the MAF sensor with Carb cleaner, which made the idle problem worse when the engine was starting from cold.
I then took someones advice and they recommend to clean the sensor with electronic cleaner rather then carb clean as carb cleaner has oil in it.
The sensor started to work better and was better when starting to from cold with slight hesitation, but very quickly started working as normal.
The revs where better the acceleration was better, overall ran beter.
When the car was warm and the error codes where cleared, no errors came back.
However when the car was started from cold the only error code that showed back up was:

051, Post Self-adaptation lower part throttle : too rich.
So I think its definatly the MAF sensor, I have ordered one from ebay, and I will change it and see if the codes perminatly go away, also will see if it performs.
Please let me know your thoughts if anyone has had similar experience.