hello, i have a 93 escort lx with 110k on it, chk engine light came on, did the tests and came up with a 181 (M) Fuel system was lean at part throttle Single, Right or Rear HO2S . this means o2 sensor so i changed that out.; still get the same fault! any suggestions from this esteemed crowd? it's hesitative when maintaining 60 mph unless you goose it hard then it cleans up for a few miles then same thing over, thing is i drive 40 mi to work on 2 lane road at 60 mph :O did the run tests and cylinders checked ok as far as the injectors. im kinda stumped, oh ya new plugs and oil this week already. would a vacuum leak in the brake pot do this kinda thing or the flapper thin that senses the air flow? HELP
thanks skidflap