Either the car is telling you that you shouldn't be driving that fast :) or there could be a problem with the tires, steering or suspension. Possibly a tie-rod end, separated or unbalanced tires, mud in the rims or something of that nature.
bad speed sensor
My 1994 Honda Accord LX (4 cyl.) gets 29 mpg when driven on the highway at around 65 mph. If I push it to 75 or 80 mpg it drops to about 25 mpg.
about 70-80 mph
80 MPH
goes 80 MPH
45 mph.
about 80 mph +
45-50 mph.45-50 mph.
45-50 mph.45-50 mph.
inner tie rods bad at rack and pinion
80 foot pounds. Almost all Honda vehicles are 80 foot pounds.
80 ft/lbs