I'm wondering if I am ruining my injectors or something. I installed my PR CAI in , um, June. Got the light within a week, all three codes get pulled, almost everytime. Sometimes its only the rear, sometimes the right or left front, its been random.

I have 130,some thousand miles now.
Thanks.

Very bad for gas.
With the check engine light on, the car runs in Open loop mode so the fuel mixture is rich. If you fix it where the check engine light goes off, you'll get much better gas milage.

You can get the O2 sensors from www.courtesyparts.com Call and tell them you are a maxima.org member and you get an additional discount. I think it cost me $130 for two O2 sensors including shipping.

I went two weeks with it on and I noticed getting 230 miles between fill ups versus my normal 310 miles between fill ups.

Dead Oxygen Sensors won't hurt the fuel injectors. However, your engine is probably running with a rich fuel mixture. This wastes gas and increases the burden on your Catalytic Converter. In the long run you risk having a clogged Cat and possibly even a fire inside the Cat. I'm not saying this to frighten you, just to make you understand the consequences of neglect.

At 130K miles your Oxygen Sensors may have reached End Of Life, and it was only coincidence about the CAI installation.