Running rough at low idle

My 1992 Taraus 3.8 GL, with 81000 miles, runs rough at low idle and takes 2 cranks to keep running upon start with giggling of accelator. At redlights have to generally put in neutral to keep running smoothly. Engine light comes on after 15 or 20 minutes of driving. Goes off when engine shuts down. Have new--intake idle control valve--egr valve--position sensor for egr valve. Also new plugs about 6 mos. Old. Yesterday when I turned on the windshield washer the engine shut down and had to turn off ignition in order to get restarted. Tech says he cannot see any carbon build-up but when was computer checking the egr valve he commented that the system showed --lean?