2005 Chrysler 300 Q&A

2005 Chrysler 300 Question: what would make my car misfire intermitenly while driving and also when ideling

has had new spark plugs and wires and a egr valve replaced -
Answer 1
Was the misfire diagnosed before the parts changed ? If so , what cyl(s) had misfire codes? Why was the EGR valve replaced? -
Answer 2
seek a diag and have codes read and do not drive this could cause eng damage -