So I accepted a new job and the last two fill ups have been from a new station I've never used they're very busy! My fuel mileage has dropped 3 miles per gallon and I've watched it over a few tanks. Nothing else has changed. Drive time and commute are the same passenger weight is the same the way I drive has been consistent. So what would cause this? Also I'm at almost 20,000 miles should i do a fuel injector cleaner or anything similar? Opinions are appreciated.