Why does my Audi A1 suddenly have poor fuel efficiency?

I've been driving my Audi A1 for a few months now and suddenly notice a significant decrease in fuel efficiency. What could be causing this sudden change?

It is possible that your air filter needs to be replaced. A clogged air filter can cause your engine to work harder and use more fuel. You should replace your air filter every 12,000 to 15,000 miles for optimal performance.

Another potential cause could be a problem with your fuel injectors. If they are dirty or clogged, it can affect the amount of fuel being delivered to the engine, resulting in poor fuel efficiency. Consider getting a fuel system cleaning to improve your car's performance.