Previous thread: http://www.aveoforum.com/forum/f108/...26/#post179389
Cat was destroyed, replaced that with a 49-state cat (California car). P0420 came back, replaced both oxygen sensors (APWI upstream and NTK downstream). Now, I get P0133.
In the morning when it is cold, the car starts but idles rough for 5-20 seconds then is fine, no code. My wife drives it to work, no issues. However, the last two days (I cleared the code each day) when driving home in traffic, she says she will begin to accelerate and it it will be rough for a couple seconds, the CEL will come on, then fine.
At high RPM's/speed, it smells rich. It does not smell rich under normal driving conditions.
I thought, oh well, dumb me for buying the cheapest upstream sensor from some company I've never heard of. I was going to buy the NTK or the Denso, but I saw that on Rock Auto they have an AC Delco one that says "ENSOR,HTD OXY w/TIER 2 FED EMIS(NT7) or ULEV2 CALIFORNIA EMIS SYS(NU2) ".
Since it said California, I was wondering do I need that particular one since this car was manufactured for CA? It says ULEV2, but my car does not fall under that as far as I am aware. I have tried scouring the internet but I have come up with nothing.