Hey guys, been too long! I haven't had much time to work on the Monte while away at college, but now that I'm on winter vacation in between semesters I should have some time to tinker around!

So on to the issue at hand,....
I have had a CEL on since the day the car was bought less than a year ago. During the summer, I had a local Autozone run a check and discovered that I had a code for hard shifting and an emissions issue simply related to having a high-flow catalytic converter on the exhaust. In New Jersey, one cannot pass the emissions part of a state inspection with the CEL on at all. The inspection center's report confirmed the existence of the two codes.

How can I reset the CEL so that it own't be on when I go to get an inspection?

I understand that one apparently has to drive 100 miles without the CEL coming back on for the computers at the DMV to acknowledge there wasn't a recent reset. However, a family member disconnected his battery to have the CEL turn off and went and passed inspection without problems.

Thanks for the help, MCF!

 

If they have to hook the OBD2 port to a computer, it will know it was recently recent because that sensor won't be back in its "ready" mode yet.

If it's a dumb code for like a gas cap and you reset that CEL, you can pass no problem because that doesn't have a ready state to get back up to.

Your options are to put an anti-fouler on the rear o2 sensor so that it reads correctly, or get the P0420 code tuned out of your PCM so it never reports.

 

I mean you could give it a shot by unhooking the battery. But I doubt it would work. If it worked for your family member then I guess you could get away with it as well. But that's not a guarantee. However you can do the same thing by unhooking the battery for longer than 15 minutes and reset the CEL. However, once you cycle the ignition 3 times with the same issue it will pop back up. So don't try to start the car then drive to the store then drop something off, and then head to the inspection station.

 

So I believe I will deleting the P0420 code for high-flow cats by having a fellow forum member do it! I haven't had the hard shifting/slipping/lagging problem in a while, but I suppose there's no guarantee that it's gone and that the CEL will actually be dimmed for once in this car's life.