Mercedes CLA Diesel Engine Power Loss

Sounds familiar. I had a similar issue with my old Opel Astra, although it was a petrol engine. Engine light, reduced power, the whole shebang. It turned out to be a faulty camshaft sensor. Were the sensor readings checked? Sometimes it's intermittent, and that messes with the engine timing and can lead to misfire.

The mechanic mentioned checking the reference value, but I'm not sure if they specifically looked at sensor readings. If the camshaft sensor is faulty, would that directly affect the crankshaft reference value? I'm trying to understand how the crankshaft sensor could be to blame if the camshaft is the problem.

The camshaft and crankshaft sensors work together. The engine control unit (ECU) uses signals from both to determine the exact position of the pistons and valves. If the camshaft sensor is sending incorrect information, it throws off the entire reference. If the mechanic suspects crankshaft, I'd advise getting a second opinion or taking it to someone who specializes in Mercedes. I ended up replacing both sensors just to be safe, but it's best to properly diagnose it.

I took your advice and went to a different workshop. They confirmed it was the crankshaft sensor. I replaced it, and everything is back to normal. The engine light is off, power is restored, and fuel consumption is back to where it should be. The repair cost me about 340€. I appreciate the help!