SMAX uneven engine running

That definitely sounds concerning. An uneven running engine with those symptoms could point to a few things. Before jumping to fuel injectors or sensors, have you checked for any obvious exhaust leaks? A small leak in the exhaust system can cause the engine to run poorly, trigger the check engine light, and lead to jerking. It might be worth a quick visual inspection under the car if you can safely do so. Have you had any recent work done on the car that might have disturbed the exhaust system?

Thanks for the quick reply! I haven't had any recent work done on the exhaust, but I'll definitely check for leaks. Where exactly should I be looking? And if it's not the exhaust, could it be a faulty ignition coil?

Okay, so if you are checking for exhaust leaks, pay close attention to the joints and seams in the exhaust pipes, especially around the catalytic converter and muffler. Sometimes you can hear a hissing sound when the engine is running if there's a leak. But be careful, the exhaust gets very hot! Regarding the ignition coil – yes, a faulty ignition coil could cause similar symptoms, but the error code stored in the memory is really important for narrowing down the issue. Without knowing the error code, it's hard to say definitively. To be honest, with the symptoms you are describing, it's best to get it properly diagnosed at a workshop. It could save you money in the long run by avoiding unnecessary parts replacements.

Thanks for the advice! I checked for exhaust leaks as best as I could, but didn't find anything obvious. I took it to the workshop, and you were right – it was a small leak in the exhaust system. Repair cost me 265€. All good now!