Mercedes CLK diesel transmission problem

Whoa, sounds rough! I had something similar happen in my old Peugeot, though it wasn't a Merc. My tranny was acting all kinds of weird, like yours. Turned out to be a faulty pressure switch. Is that what you mean by oil sensor? Made the car think it was low on oil, even when it wasn't. Might be worth checking!

Thanks for the quick reply. By 'oil sensor,' I mean the transmission oil pressure sensor, which I think includes a pressure switch. Could you tell me more about the specific symptoms your Peugeot had and how you knew it was the pressure switch? Did you use a pressure gauge to check it?

Okay, pressure switch is probably the same thing then! My Peugeot was shifting hard, like BANG, and sometimes wouldn't shift at all. Limp mode was common. I didn't diagnose it myself, tbh. Took it to a shop and they hooked it up to their fancy computer. They told me the pressure readings were all over the place, even after they checked the oil level. They replaced the switch, and boom, problem solved. I'd suggest a visit to a workshop...

I appreciate you sharing your experience. Based on your advice, and after further consultation, I decided to take the vehicle to a qualified workshop for professional diagnosis. It transpired that the transmission oil pressure sensor was indeed faulty, and the oil level was slightly low, as suspected. The sensor was replaced, and the oil level was corrected, resulting in a total repair cost of 365€. The transmission now operates smoothly and without issue. Thank you again for your assistance.