I have a 1999 Jeep Grand Cherokee Laredo 4.0 , Went to work this morning turned off the ignition for 3 minutes . Started it back up and the check engine light came on , started shaking bad , let sit at work all day (9 ) hours started her up and shaking like it was going to come apart an the check engine light came on . Died once when I stopped and started shaking the moment I got her going again. I change my oil every 6000 miles , I never let it get below a ½ a tank of gas got codes #2 or #5 ,coil pack, or fuel injector.