I have had a problem passing emissions in IL. I have a cheap obd2 scanner and was having trouble clearing the p0442 code only to find out it is a permanent trouble code. I ran a smoke test and repaired the leaking EVap fitting. I then drove for weeks waiting for the evap readiness monitor to OK and it has just completed. However, I still see the code p0442 stored. All monitors are complete and there is no engine light on. I had expected the code to clear after I made the repair and the evap readiness completed. I need to get it back to test emissions so that I can pass and re register my vehicle. Do the permanent codes clear on their own? If so, how long does it take seeing that all monitors are complete and no light is on.
Thanks, Ed
***I am not a professional mechanic but try to do my own repairs.