This is a reply to my post that isn't active anymore. I was getting spark knock after spark plugs were supposedly changed. I got alot of answers that didn't add up at all and someone mentioned egr valve. I did a code scan and gave egr and 02 lean. I tried cking the plugs myself and snapped a vacume line. All this added up, so i cked, replaced the vacume lines and prob fixed. While this guy was changing the plugs like i was must have snapped one of the lines. I really appreciate the help. Hopefully i'll be able to haelp someone else