It makes it suspicious, that's for sure, especially since most of the codes are from the MAF sensor and IAT. I don't know if that would cause the O2 malfunction, but it certainly doesn't help.
If you pull your passenger's side kick panel, the ECU is there, and there's a tag with the catch code on it. If you pull the code off the sticker, I can tell you what year the ECU is from.
In all honesty, if it was me, I would keep the car like it is, the MAF and injectors are a decent upgrade on earlier cars, and I'd start saving for a dynotune.
2001 Dark Highland Green Bullitt [email protected] naturally aspirated on a bone stock 2V longblock
Under Reconstruction for RS275 Drag Radial Class Pushrods and Powerglide Coming Soon If it weren't for physics and law enforcement, I'd be unstoppable.