have you asked your master mechanic friend if he has any ideas??

 

I was going to ask the same thing.

Personally with both of those codes I would either suspect that the new 02 sensor you put in was faulty or that there are some wiring concerns you need to be chasing down.

 

Yes, but I moved for school about two hours away from him, so he hasn't been able to see it, and wont be able to for another 3 weeks. I have updated him daily, and he is baffled without actually seeing the vehicle. My roommate is a non-certified mechanic, if you will, and we have been working on it, but nothing is working. Until the semester is finished, I am unable to take it to the master mechanic.

That being said, I am really trying to avoid that, because that will cost a lot of money, and the car will be hours away.

I was thinking an electrical problem, but Idk. Could it be a bad cat converter when it's idling weird? It runs really smooth now that the new 02 sensor are i it, but still idles rough.

 

Since the two codes you are getting have to do with the O2 circuit not having activity, I'd look at the wiring starting at, and leading away from, the O2 sensors and see what's going on with those first. They could have become melted or damaged in some other way. <-- That is a common cause of those codes on any car.

 

I have a 2000 Neon with 182,500 miles on it. I started having the rough idle two years ago, it would drop RPMS like there was no tomorrow and then go back to normal. I took apart the throttle body and cleaned it out with throttle body cleaner. It was so gummed up the throttle plate kept sticking while trying to idle, hence the idle problem. I also did the MAP sensor at the same time. It solved the issue, haven't had a rough idle since. I still have the original O2 and Oxygen sensors and Manifold/Cat...the rest fell off last winter, ha.

Try this, it will cost you $3.50 and an hour of your time. If that fails, try the idle screw.

 

I second Darth, especially since it's only idling rough now. My brothers neon had melted wires, i on the other hand have been spared that headache.

 

same here I have 230k miles on my original exhaust, cat & 02 sensors.... never had a cat or 02 sensor code yet... but am replacing the cat this summer since the magnaflows are so cheap these days