Resolve themselves? Didn't know another way to phrase it.

Have an '04 Discovery that has been throwing somes codes and have not been able to pass inspection. New MAF seemed to fix the lean codes but I still have a PO441 showing.

Question is: Will the CEL go out after it is resolved, or must I clear the codes with the UltraGauge manually? I would prefer not to clear them if I do not have to since I would need to go another 100 miles or so to cycle the system before getting it inspected again.

Anyone know about this?

 

It is my understanding that you need to clear the codes. Hate to make you paranoid... But here I go- I had an 03' that had to be driven over 2000 miles before the evaporative readiness monitor was ready. My current 04' took just over 600 miles.

Good luck.

 

That would be really, really bad.

 

I always clear codes.
Active fault will soon come back, but a system not ready or pending can take a bit to straighten itself out

 

MOST codes will reset the light themselves if the problem goes away, after about 3 cold starts. The code will still be stored on the computer, but the light will be off. I'm not sure how emissions checks work because we don't have them here, but I'm guessing they hook up even if the light is off to check for the readiness, in that case they may notice the old codes. but maybe they will see they aren't current anymore and not cause a stink. I personally wouldn't want to risk it.

 

500 or so miles on mine before it would pass. state emission. if you do have emission testing they usually have a set mileage amount where they consider them clear.

they wouldnt want you waiting in line with an OBII scanner clearing codes before you enter the bay for inspection

 

So how did you know that it took so many miles? I have not been able to figure out how many miles are in a cycle for me. Sometimes it seems like they came back after 75 or so miles, other times 150 miles.

Guy at the testing site said it just needed to be a cycle and the light off, so codes on the computer.

 

every state is different

 

I bought an ultragauge that shows the readiness monitors. The evaporative is always the last to be ready. Harbor freights little red OBD2 CAN reader shows it as well.