I have a couple codes that I need help finding the problem for P0401. P0402 P1406 p0171 and p0174 ,, I know all the codes are very related . My egr tubes would keep blowing off so I put clamps on all four ends to keep them from blowing off and I believe that could of added 2 of the codes ,, I replaced the egr sensor with a metal one from the savage yard due to me breaking one end of the plastic egr position sensor,, Any help would be great what should I do