Weird jerking C220cdi
 

Hello all!
Car is 2009 C200cdi manual estate.
I've had this odd issue for a while now. Occasionally there are odd slight jerking when driving. Not so big difference but noticeable anyhow. Starting the car or anything wont help. On next day it's probably gone.

I notice sometimes some similar in second gear if is somewhere between 1100-1600rpm. Not always. Usually in city driving. I did not gave it too much attention because i thought that is just under power. Is true that's a strange behavior. I am not sure if is something "normal" or not. This happens rarely. I usually change next gear when I'm over 2300rpm. Also on manual om651

Ps: i had similar behavior on the previous car that was also a diesel-manual gearbox

Yeah, that is weird.. Idle is totally normal. Did you ever get any cure for the issue?

I do not think that has to do with brakes. This happens when the engine is under power curve ( 1000-1500rpm). More likely has to do with injection map, or flywheel. That's my opinion. At least in my case tis is not a issue. Just change gears higher in rpm range. (Over 2300rpm depending of driving conditions)

In my case it doesn't effect if I'm driving 3000 or 1500 rounds. When the fault is on it's on and I can feel it clearly.
My wild ques is that there is some sensor (throttle pedal etc) which is causing the whole thing. Why I think so; The issue is occasionally, it won't happen every time when I'm driving. In a case of flywheel/injection map it would come every time.
But like I wrote, the oddness is that there are no sign of any faults in error log..

Could it be the torque converter locking up? I think mine does it 2 different levels and it kind of jerks forward.

In gearbox? Is there that kind of converter when it's manual..?

So sorry, missed it being a manual. No, no torque converter.:hammer:

troubleshooting
 

Odd combination (lurching and brake smell).

Isolate which brake(s) may be sticking, suspect only a front caliper would have enough effect to contribute to a drive ability problem.
At 9 years old you may have turbo vanes sticking or the vane ring worn.

Another possibility is a leaking boost host, look for oil and feel for split.
The boost control modulation may make the air pressure flutter, trying to get requested/actual level right when there's a non-catastrophic leak.

Yes, I’ve tried to feel what would be the warmest disk but no luck yet. They all seems to be very warm and that’s why the smell.