C200K nearly stalls when braking

[steve pratt]

Hi,
My 53 plate C200k Automatic nearly stalls when coming to a stand still. Sometimes if i accelerate from stop and brake immediately the engine appears to hunt and oscillate for a few seconds gradually decreasing. There is also a slight vibration at tick over now when in drive but not in neutral.
Split vacuum pipe under air cleaner was replaced recently which has solved the erratic tick over.
Any ideas please.

 

[ernie]

Check the remaining vacuum pipes, particularly around the servo. Does the servo hold the vac after the engine is switched off? I.e. after say half an hour and you press the brake pedal, does it go solid after a few presses, or is it solid immediately? This might point to a faulty servo.

On the other hand, it could be something unrelated which might show up if the fault codes were checked.

Ernie

 

[BlackC55]

There is also a breather pipe and a one way valve under the inlet manifold that splits. Needs a Star to read codes and data.

 

[steve pratt]

thanks for input. the breather pipe and valve were split and changed before Xmas which cured the erratic idle nicely. This vibration is as though the tick over in drive is too low as it disappears in neutral as the idle increases slightly. Is there any idle adjustment i can do. I cleaned the throttle body last summer but maybe an air filter change could help now?

 

[ernie]

As above, you really need to have the codes read. Something is wrong that is causing your idle problem and until that is done, you could be spending money unnecessarily.

Ernie