Went bad.

I've heard the aftermarket ones don't work. In all the years this car's been out i'm sure someone has replaced one...

It's a 2000 if there's any differentiation amongst the years.

 

Get the OEM part (Not sure if its NGK or Bosch), replacing the primary and/or secondary is really really easy. Just use some PB blaster before you attempt it.

I helped Sean_Halla replace his, the hardest part was unscrewing the bolt, it was stuck on there like glue. After that it was really simple.

If you have a jack, stands, and basic Metric tool set, either a wrench or an O2 sensor socket, I can help by pointing out what you need to do

 

I know you said primary, but I replaced my downstream (the one mounted on the cat) with an NTK/NGK I found on Amazon. Cost me $75, and to my surprise, exactly the same as as the one I that was bad. Reading the boards, I think that if you stay away from universal O2 sensors, you be ok, 06 and up AP2 seem to be more sensitive to what you use. Another thing I learned is that the cat will fail and destroy the O2 sensor, as was my case.

 

Usually it happens the other way around -- usually the O2 sensor fails, which causes the engine to run too rich, which then kills the catalytic converter.

 

i bought a aftermarket Delphi brand for my secondary from www.rockauto.com and it works great... No cell and no issues... Going on about 6 months since i replaced it...

Dre

 

Oh yea and i paid like $28 shipped

 

Yeah Rick, the ceramic in the cat came loose, slid back, sheared off the tip of the O2 sensor, and caused CEL. Others on the technical forums have seen the same issue.

 

Wow, that's a new one to me... Crazy!

 

My primary sensor is going out on my S2000. Much as I hated to pay up, I ordered OEM due to mixed results I've heard about aftermarket ones. I believe the primary is more important for tuning, so I might be willing to go aftermarket if/when my secondary goes out.

 

How much did the OEM one set you back? $300?

I've been trying to locate one online with no luck.