How do I fix the rough idling issue in my Ford Focus?

I recently noticed that my Ford Focus has been idling roughly. It feels like the car is shaking and there is a strange noise coming from the engine. I've checked the spark plugs and air filter, but they seem to be fine. Could this be a sign of a larger issue and how can I fix it?

It is possible that you have a problem with your fuel injectors. Try checking them and if they are dirty, clean them or replace them. This should help smooth out your idling problem. Also, make sure to regularly service your car to prevent future issues.

Check your engine mounts as well. If they are worn out or damaged, it can cause your car to vibrate and have rough idling. You can replace them yourself or take it to a mechanic to do it for you.

Another common issue is a dirty throttle body. Try cleaning it and see if that improves your idling. It's a simple and inexpensive fix that can improve the performance of your car.