Hi,

I have a B200 2009 automatic (w245 with 722.8 transmission).
I’m having a weird problem. If I leave the car running while in park for few minutes then drive, it would shudder and not pick up speed. If I turn the car off then on again, problem disappears!

I can easily recreate the problem by running while transmission in park for few minutes. I did that and started to shudder. As I was driving, I shifted to Manual control. I found out that if I shift to lower gear (rpm above 3000), problems is gone, but if I shift to higher gear (below 3000 rpm), problem comes back!

I’m not sure if it is a valve body, TCM, torque converter or something else. I think I need to fix it before it gets worse.

thank you for your help.