I have a 2005 ford focus I bought last June, it has 11,500 miles on it and gets about 22 to 23 mpg highway. the question I have is I have noticed the past few days the od light flashes amber color when driving or idling is this normal? I like the car but am not real happy with the gas mileage seems like od cuts in way early around 40mph. I am use to od not kicking in until around 50 to 55 on the highway...Is my car getting sick or is this normal for a ford??

thanks