How to troubleshoot a check engine light in my Audi A4?

I recently noticed that my check engine light came on in my Audi A4. What could be the cause and how can I fix it?

The check engine light can signify a variety of issues, ranging from a loose gas cap to a major engine problem. The best way to determine the cause is to use an OBD-II scanner to pull the diagnostic trouble codes (DTCs).

Having the DTCs scanned by an experienced mechanic can provide you with more accurate and detailed information about the issue. They can also suggest any repairs needed to fix the problem.

One of the most common causes for a check engine light is a faulty oxygen sensor. This small part is relatively easy and inexpensive to replace, and can greatly improve your car's overall performance.