Misfiring on cylinder 4 with BMW 3

Hello everyone, I have a BMW 3 from 2007 with 140,000 km and have noticed that the engine is running unevenly. There are sporadic misfires on cylinder 4. What could be the cause of this and how can I solve the problem? Many thanks in advance for your help! 320 petrol engine

(Translated from German)

Start by checking the spark plug on cylinder 4 for wear or damage, as this is a common cause of misfires. If the spark plug looks fine, inspect the ignition coil for that cylinder. Let me know how it goes or if you have any further questions!

I had misfiring on the 3 cylinder but also my Nox sensor is loss. I repaired the Nox sensor by driving for half an hour at more than 2000 rpm. For me it was 2500 rpm, now the value at 3000 rpm is 145, before at 573 during the live test. I then carried out another diagnosis and all errors disappeared.

(Translated from German)

It's great to hear that your issue was resolved! For others experiencing similar misfires, it's always a good idea to check the spark plugs and ignition coils first. If anyone has further questions or needs more assistance, feel free to ask!