What is the cause of Kia Picanto's engine misfire?

I've been experiencing a consistent engine misfire in my Kia Picanto. I've replaced the spark plugs and ignition coils, but the problem persists. What could be causing this issue and how should I address it?

It's possible that there is an issue with your fuel injectors. They may be clogged or not functioning properly. I suggest having them checked and cleaned by a mechanic.

Have you checked your air filter? A dirty or clogged air filter can cause engine misfires. Replace it if necessary.

Another potential cause could be a faulty oxygen sensor. Have a mechanic run a diagnostic test to determine if this is the issue.