i have been trying to my figure out my check engine light problem its a code 0401 i think. saying it s an egr problem.what else is going on is my blender box sometimes doesnt close the floor vent.i have read that a vacuumn leak can cause this code to pop up i have changed the egr but code came back by the way i have 19 vac w/ a obd2 reader. what should i check next . i think the blender box is hard to get to but thats probly the culprit what should i try next