won't pass inspection..inspectionsays oxygen something fuel something & something else i don't remember .it failed 3 need to get one to work.advance & auto zone checks..we have changed the knox(?)sensor it said first,and also changed spark plugs and cleaned egr valve and ports. light went off for a short time and came back on. now auto zone checksays po404 & po405 fault in the egr position & egr pressure sensor, open or short circuit condition. are there any suggestions you can give us to try? is there such a thing as egr sensor?advance auto did not show on their list,maybe it just isn't something they carry? help please . thanks for your time..
May 3, 2011 at 10:51 PM