Taking car in for inspection, have SES due to unplugged rear O2 from exhaust - clear it using OBDII, but I know the car takes time to go through some sort of "reset" cycle (I have taken the car in before right after clearing and they hooked it up and said "did you just clear this?") - pretty sure I have to drive the car around for <x> amount of time before the computer goes back to normal.... and then again for <x> amount of time before SES will re-appear with code.

Please fill in above <x>'s for me if you know for definite - thanks.

 

Probably a week of driving, itll return to normal, then probably half a week for it to reshow the code..

I reset mine for a P0420, which nissan said, its my cat and 2 o2 sensors. i drove mine for a week, and it hadn't come on so, i figured i guess i could try emissions, and i passed emissions, while one of the status reports said "Catalyst : NOT READY" then maybe like within the next week, my CEL came back on for the same P0420..

 

if the light comes back again, there is a problem

 

Thanks.

 

p0420= catalyst system efficiency below threshold (bank 1)

Catalyst: not ready = indicates that the monitor hasn't completed its diagnostic testing.

 

I had the same problem. reset with scanner and drive like 35-40 miles and go for inspection.

 

some states require that all vehicle monitors have run and completed their diagnostic testing before it can be tested for emissions.




ct doesn't lol

 

Same problem had a bad 02 sensor and bad CAT and tried fooling the emissions by reseting and driving and taking it to the test but after like the 8th time they told me that it wasnt ready i decided to change everything and no light after 150 miles and 5 days of changing it im going back!

 

fix the problem

 

NOW IN A problem like this, would an aftermarket exhaust fix the problem...a full aftermarket exhaust that is (not just cat back)?

 

Usually it takes 60-100 miles of driving for the computer to not show it was recently reset.

 

If you eliminated the cats then, probably.


To the OP, you need 2 trips, no matter how long. Turn on / turn off. It should be ready now. if the code comes back, then

 

i took my car to inspections today and still not ready. It has been 7 days and about 200 miles what do i do?????

 

Since?

 

who are you and what problem are you having

 

Okay what needs to be done is what has been mentioned before, and its called a drive cycle. The car must have the code cleared, driven between 55-60 mph w/ NO cruise control for atleast 15 mins and then the computer should reprogram itself. I have done many of these drive cycles and 95% of the time, if you do it properly as i stated, the issue will correct itself. Its not a guaranteed fix but thats what I have been taught. Best of luck!

 

you must fix the issue before "clearing codes" otherwise the CEL will come back on.
Consequently why bother clearing codes which contain valuable information if there is nothing wrong, the computer will know this after a short time and turn the light off by itself

 

since i last changed the catalytic converter and O2 sensor

 

fixing the issue should be common sense.