Typical repair for Code 21

[Banshee365]

Hey guy's. My trusty paseo is falling apart this week. The radiator has sprung a pretty bad leak on top of the radiator. Going to buy one on eBay with a lifetime warranty for $90 free shipping. The pass. side outer CV boot has also ripped and is slinging grease everywhere but it's not ticking yet. I bought a new boot but realized I would have to destroy both boots as the outer joint does not come apart so I'll just wait until I can afford a complete new axle with lifetime warranty for $70 at Advance Autoparts. Anyway's, here's what just happened:

Driving home tonight the CEL came on. I got home and retrieved the code, it's code 21. My manual's say it's an O2 sensor problem and the fixes are wiring, sensor, or ECU. What are the typical fixes for this problem? The car has 205k miles and run's amazing. I hate staring a the light and I will not remove the bulb. I want to make it go away the right way. Has anyone had this code and what did you have to replace to fix it? Are the aftermarket o2 sensors okay or should I just go OEM? I'm handy with a solder gun so that's not problem if the aftermarket just comes with a pigtail. Thanks!

[96paseo]

OEM plug and play = peace of mind for an O2 sensor. I don't bother with aftermarket sensors for sake of the frustration and headache if it doesn't work. The sensor is probably original and its not unusual for it to go bad at that mileage. My upstream went at about 185,000 and the downstream at about 225,000. +1 on getting a new set of axles. Its way easier than rebuilding/repacking the boots and CV joints. If you've got plenty of time on your hands, rebuilding them isn't all to bad. And cheaper. As far as an Ebay rad goes, cross your fingers it doesn't crap out in 1-2 years. I've read many a horror story about them. Good luck.

[hairba11]

i've had one of the ebay radiators in my 92 'seo for about 5 years with no problems.
I'd go OEM on the o2 sensor, I went aftermarket in my integra and was putting in one almost every year,