Quote Originally Posted by BillBoost37 View Post
Your post is a bit confusing to me, seems like others as well.

Your title says you want help with a lack of a rear O2, then you mention it's already deleted and was running perfectly.
You thought you could to better and couldn't, so you need help. With what do you want help? What did you do that didn't work better than how the car was previously running/setup?
Obviously the car leaks (it's a 3800 so that's not a big surprise, but whatever) and you think you may want a dyno tune. If you undo whatever you did, wouldn't it run perfectly again?

See where I'm going.. you aren't quite describing to us what was done or how the car isn't running right. Being an internet forum, we can only read and many times need a lot more info.
The car was tuned for not having a rear o2, I got an intense canned tune not thinking about it, and now the check engine light is on. I thought I was doing good by "updating" the tune but it only made things worse.