C30 Engine Misfires

Rough running, check engine light, and jerking are certainly concerning symptoms. These can be indicative of a combustion misfire. Do you have access to an OBD2 scanner? If so, could you check the error codes and let me know what they are? Knowing the specific cylinder misfiring, if any, would be useful.

Yeah, I borrowed a scanner from a friend. It's showing combustion misfires. What does it mean? Is it still likely to be the fuel pump?

Combustion misfires can stem from various sources, although a faulty fuel pump should not be discarded from the list of possible causes. In my experience, when multiple cylinders are misfiring, it often points to an issue with the fuel injection system. Considering the symptoms and mileage, I'd advise having the injection valves/injectors inspected by a qualified mechanic. It is difficult to pinpoint the source of your problem without appropriate diagnostic tools.

Thanks for the help! Took it to a shop, and it turned out to be a defective fuel injector. Cost me 515€ to get it fixed, but it's running smoothly again.