Hello All,


I would wonder if anyone has yet found a solution on this issue yet. After reading several forum posts and attempting to find some Technical bulletin about this issue I thought maybe I can get a better help here based on experience.


I actually bought a W203 C180K FY2005 with 90K km done. From the information I could find based on EPC the engine is M271.946.


When braking in traffic or red light traffic stop, when parking I get a rough shake at low RPMs when shift is on D or R whatever the position is. Sent my car to the dealership and from the diagnose the result was 'mixture too rich' which from what I know this should be due to air leaking but couldn't find any broken air pipe.


Anyway, after this diagnose I decided to remove and clean the throttle body, repair oil leaking from the vacuum pump which is located in the rear part of the engine (a nightmare to be removed). In addition changed the oil in order to be sure none of these could influence on the issue.


After 10km of ride, the problem came back on, and still very disturbing (making you feel like the engine is being shut off). Also this vibration followed by low RPMs (like500rpm or something) is driving me crazy.


Any suggestions on how to fix this?


Thank you in advance!

Did u solve it ???

Not yet mate, just a small improvement.
Please check below thread for detailed interventions https://mbworld.org/forums/c-class-w203/486212-722-6-transmission-delayed-engagement-stop-sign-when-cold.html

they are talking about transmission....... and that the transmission what caused the engine looks like its want to turn off when u breaking and its come worse if the Ac is on .
for me this happened always even the car cold or warm .
i asked some one about this issue and he told me to clean the body throttle bcz he told me that the problem in air system,so i will start in cleaning , i will do it and update u

I guess a good start would be checking the air system. Maybe from the throttle body to the intake manifold could be some air leak that causes this problem. If you're going too deep in air leak inspection I would suggest changing intake manifold gaskets. In addition if the car shows lost power, it would be a good idea checking exhaust system too including O2 sensors. They often are the cause of many troubles in these vehicles.


Looking forward to hear back from you.

the electronics in the TB are sealed but eventually they allow moisture in and wreak all sorts of havoc on the throttle mechanism. Consider swapping the TB with a known good one or find a good used one.


Vibrations at a stop when in gear could be old/bad motor mounts.

I would suggest provoking the car to stimulate the vibrations monitoring engine RPM visually on the odometer or preferably with MB Star.
If chances are that rpm go around 450-500 the engine may even shut off with gear engaged. Also, testing the car on traffic and drive for around 2-3 hours without turning the engine off would make the problem more evident.


If Opelveve is experiencing the same problem as I did sadly I must say that, the road to the solution is going to be quite long.

to be clear for every one again my friends...
the problem wn u breaking and want to stop for a red light traffic for example u will feel that the engine looks like it will go off and the RPM go down alote.....and the peoblem come worse if the AC is on.....
i want to do a whatsapp grouo for mercedes benz
give me ur numbers guys to add u
and if any one want to come to the group just send me a whatsapp msg and i will add u .
00971506740840

and if i drive the car in Manuel and its on 1st gear this happen with me every single time i want to stop my RPM go down

Yes, you're right on the symptoms. Check my video below and please confirm if you're experiencing exactly the same.

u have whatsapp

I thing it's better keeping the communication on this forum showing some respect for its contribution and maybe we help others too

I cleaned my TB and still have the same problem Drive + AC + break= vibration + low RPM (low RPM just for seconds )

Any help guys

My friend to all who suffer engine vibration or low RPM
Just change the hose under the kommpresor its 3 pieces

Could you please explain more about solving this problem.

Hi, can you please explain how you solved the problem.
Thanks

Opelveve is referring to the "$12 vacuum hose" ... which should be documented in another thread in this forum.

I did something today that could have helped or solved my problem here.

Chasing down a slow oil seepage on the left side of the engine, I removed the air box and discovered that the top engine crankcase breather hose -- the one that goes from the valve cover to the MAF air tube -- was installed backwards! This was likely done by the dealer many years ago. The tube appears to have one opening slightly smaller than the other, so when installed backwards, the top connection is way too tight, and the bottom connect was loose and jiggly.

Here is a pic of the oil seepage coming from that joint:



I cleaned everything up and installed the hose correctly, with the elbow up at the top:



The bottom fit more snugly now.

Put everything back together and went to run some errands ... and the idle drop issue seems to be gone now.

Now, in addition to installing the hose more tightly, I did one other thing -- I disconnected the ECM from the car harness in order to take the airbox out. That presumably would have reset the ECM. So I am not sure at this point which one is "fixing" things.

But the car stops well, seems to idle just a bit higher than before while at a stop with car in drive, no effect when I press on the brakes, and when I turn on the rear defroster (which always used to give a shudder) the RPM dips to low 600's but no shudder).

I can report back in a week to let you know if this has stayed good. If not, then I would guess it's the ECM reset that helped, maybe restting the tranny programming until my driving habits bring back the shudder :| But if it stays fixed, then maybe it's that darn hose ...

whats the name of the hose that the green arrow is pointing to? I bought my car its running fine but smokes from were it that hose is connected, en my car doesn't have it , can some one tell me what is it call en where does it go to conect ?

It should be 2710160481, "breather hose".

Btw I did an oil change a few months ago and everything is still dry back there.

thank you for the replay ✊✊✊

Has anyone managed to solve the problem?

0844023431 please add me