What is the best way to increase the mileage of my Ford Mondeo?

My Ford Mondeo has been getting worse gas mileage lately and I'm not sure why. I always make sure to keep up with regular maintenance and I drive mostly on highways. What could be causing this decrease in mileage?

First and foremost, make sure you're keeping up with regular oil changes and tire rotations. These are essential for maintaining good gas mileage. Also, check your tire pressure frequently as underinflated tires can greatly impact fuel efficiency.

Consider getting a tuning performance chip installed in your Ford Mondeo. This can improve gas mileage by optimizing the engine's performance.

Try to avoid heavy traffic and stop-and-go driving as much as possible. This type of driving can significantly decrease gas mileage. Also, avoid carrying unnecessary weight in your car as this can also affect fuel efficiency.