So I did it and it flashed 1 then 2. But the codes start at 13. Does the CEL have to be on when you check it? The light comes on then goes off again when I turn it off and restart it. So do I need to take it out and try to get the code to come back on and then check it?
---------- Post added at 01:27 PM ---------- Previous post was at 01:17 PM ----------
NM. I didn't know that it flashes the code 12 3 times before it actually gives you the trouble code.
Good news is that it was what I figured; an EGR problem. In the past, I've never gotten too worked up over EGR issues, should I worry too much about it now on the Tahoe?