HELP,,, 401 egr insufficent flow code driving me nuts, plus the loss of fuel economy. ive changed egr valve , cleaned the air tube , cleaned the o2 sensors .I have also done plugs and wires , there is a slight miss when service engine soon light is on , also according to reserch of my own this vehicle should be getting around 19 mpg in city and 29 on hwy , instead im getting 10 mpg no matter which im drivingI am at a loss. Can anyone help ?Edited by: winderside