How do I fix the automatic transmission in my Ford Fiesta?

I've noticed that my Ford Fiesta's automatic transmission is acting up, with delays in shifting and jerking while driving. How can I diagnose and fix this issue?

You may be experiencing issues with your transmission fluid. Check the levels and color, and if necessary, get a transmission flush. If that doesn't help, it could be a mechanical issue.

I had a similar issue with my Fiesta's transmission and it turned out to be a faulty solenoid. Get it checked by a mechanic and replaced if necessary.

It could also be a problem with the transmission control module. Have a professional diagnostic test done to determine the root cause.