A little info on my car, 2001 z28 Camaro. 232/238 comp cam. full bolt ons. auto... I have had help tuning the car through a friend of mine and I also rented the dyno locally to dial it in on the dyno. It ran great then started to have a stumble when going wot from a stop. I noticed shortly after that it does the same thing when I rev. basically what happens is when I rev it will go extremely lean and sputters. (pegs the wideband at 22.4) then around 2000 rpm it goes normal. but once I let off and the rpms fall and goes back to idle it stumbles and tries to die but usually it catches and will idle normal but then the afr will be in the mid 11 range idling and takes a while to go back to stoich. this is only when I rev it hard. if I ease into it then it wont have this issue. I did have one code come up and was a o2 bank 1 sensor 1 low voltage. I cleared the code and haven't had the code come back. im thinking its a bad o2 sensor but I wanted to see if anyone else had this type of issue. and if it sounds like its tune related or if its a symptom of o2 sensors...