Ok, so my check engine light was constantly on giving me the air injection fault code 11. I bought a check air valve and replaced and the problem was fixed. I guess I decided to swap out all my vacuum lines one day and then my CEL light came on again giving me the Air injection code again. I was trying everything to fix it for months and months. I bought a new air diverter, I seafoamed the hell out of my car, and I was just about to buy a new O2 sensor (not cheap) until I decided: "let me go out and give it one more look before I spend money on a 15 month new O2 sensor that was replaced in October 2009." I reset the light, checked all the vac lines, took off the diverter, checked the smog pump, and everything was good. Turned the car on and let it run and WALLAH! the light comes on again. Stumped, I decided to look at the picture of my engine that I took when I first had the CEL code and cleared it with the check air valve.(I always take pictures of everything under the hood before I replace anything)....Then it hit me: in the picture my ca valve is black on the top, white on the bottom.....as I stand there, I realize my mistakie, I took off the check air valve and flipped it around, reset the code and drove the damn car for an hour and no light! I had the check air valve on upside and didn't even realize it!
Moral of the story......the simplest answer can be used to solve a complicated problem