you have a pm tony. thanx. i did look it up. what i meant was how do i take care of it? the code came up IMMEDIATELY i replaced an O2 sensor.
LOL. Give me a few minutes, please! (to edit and add more info). I just read your PM. You also mention rich codes, P0172 and P0175. If you have bigger injectors and a different fuel pump, you may have to get a
tune to take those items into account.
For a "regular" engine (and OEM fuel injectors and fuel pump) in an original PCM, you may be looking:
1) Dirty air filter
2) EVAP canister failed (full of fuel)
3) Fuel pressure too high, contaminated or leaking fuel pressure
4) Bank 1 (Firewall side) Upper O2 sensor contaminated or coated with silicone or moisture.
If this happened to my car, the first thing I would do is change the air filter and see if it helps.
Then I would change out the Bank 1 Upper O2 sensor. Maybe the one which you installed recently was defective or got contaminated (or broke) while you were installing it.
Then I would do a real time scan to see what the fuel injectors are doing. If any "look" funny, I would do a UIM cleaning, in the guise of wanting to visually check the fuel injectors. If you have to replace any injectors, you will have to remove the UIM anyway.
If the EVAP canister failed, you should get some EVAP codes too.