Project 'orange roadkill' (bent valves rebuild & more)

[06T200]

Do you recall if you were seeing the rich trim codes (P0172/2188 in my case) in addition to the P0340 sensor code?

[xintersecty]

I only had the P0340 code. The sensor was working intermittently. Right now my cat has died and I am getting the P0420 code. My gas millage has gone down to 26/27 from 31/34 highway. That really sucks. So I am wondering if my injectors are faulty and running rich or I have lost compression (I run that biatch hard) or I have a tooth off on my cams (from when I changed the timing belt).

So I was not getting the rich trim codes. I wonder if replaced your injectors or not. Maybe they are getting old?