I have this highlander 2011,bought recently with about 7,000miles on it. suddenly i notice poor performance in the drive, i usually do 16-17 mpg city on it and i enjoyed the smooth ride all along. but now i hardly do 13-15mpg city on it and i have to press hard on the pedal more often to make it move faster ......dragging noticed!!!

so i had it diagnosed with the following code errors, P1605, P1604 and P 1603 respectively and was told the codes were history problem and were cleared
still the problems persist.