Citan engine misfire issue

I'm new here I have a Mercedes Citan from 2014 with a gasoline engine and about 210907 km on it. Recently the engine started running rough and the check engine light came on. When accelerating the car jerks and it feels like it has less power. I read the error codes and it shows combustion misfires. I already changed the spark plugs but it didn't solve the problem. Could it be the fuel pump?

Rough idle and engine misfiring can be a real headache I had a similar problem with my Citan a while back. While a faulty fuel pump could indeed be the culprit, there are a few other possibilities to consider before jumping to that conclusion. Did the misfires occur on all cylinders or just one? Have you tried checking the ignition coils? Sometimes a failing coil can cause misfires. It might be worth a shot to inspect them for any signs of damage or corrosion. Also, what about the air filter? A clogged filter can sometimes lead to performance issues. These are just a few things that I would personally check before suspecting the fuel pump.

Thanks for the suggestions. The error code indicates misfires on multiple cylinders. I haven't checked the ignition coils yet How would I check them and is it difficult?

Multiple cylinder misfires is indeed concerning. Since you're experiencing it across several cylinders, I'd lean away from individual coil issues, though it's still wise to inspect. Checking them involves using a multimeter to measure resistance, or swapping coils between cylinders to see if the misfire follows the coil. But, since you mention widespread misfires, I'm thinking it might be the injection valve instead. Given the symptoms, it could be the injection valve/injectors themselves causing the problem. I'd honestly recommend taking it to a workshop for diagnosis. They can perform a proper fuel pressure test and injector testing to pinpoint the issue. Okay thanks a lot for your help I took your advice and brought it to a workshop. They confirmed that it was indeed a defective injector. The repair cost me around 515€ but now the engine runs smoothly again