Speed limit “LIM” doesn’t work –> Car doesn’t pull anymore!

Hi guys, I have a question. I have a SLK 230 R170. I was in the workshop last week because my car didn’t do a clever kickdown and had total power loss and at the same time the “LIM” no longer went. Mistake: – Lambda probe defective –> replaced – Air flow meter oiled –> cleaned + hoses rinsed Ok.. Then everything went again. Now, 1 week later, the same! LIM function no longer works (it just comes strokes and car beeps) and it no longer pulls, no more clever kickdown (only weeks later it shuts down) What can that be? 🙁 Thank you for your help! LG, Alex