I have a COBB AP V2 with the OTS stage 2 map provided by COBB installed on my 07 STi, I want to go back to my stock map that was downloaded into my AccessPort to see how much of a difference there is from just a turboback to a turboback with a stage 2 map. The thing is that I don't know what option to choose. When I hook up the AP to my car and run the AP, there are about 2 or 3 different options to reset the ECU. Do I go into the Change Map setting and choose the Stock Map? or do I have to Uninstall my AP or do I choose the option to Reset My ECU.

Which one do I choose?

1. Go into Change Map Settings and go to "Stock Map" which I downloaded from COBB's Website?
2. Go into the Unistall AP Menu?
3. Go into the Reset ECU Menu?

My other question is that I am running a 3" Catless Invidia V2 Bellmouth Downpipe, 3" COBB SS Catback System and an AP V2 with the OTS Stage 2 91 Octane Map. I have a small exhaust leak from my midpipe to my downpipe. Currently I am running about 15.X-16.X PSI on my Stage 2 Map without a protune. Does about 16 PSI sound right? Cause on COBB's website it says boost target for Stage 2 91 Octane OTS Maps run about 18 PSI tapering down to about 15 PSI. If I get my exhaust leak fixed will it do any difference?

My last question is that since I have an exhaust leak from my mid to downpipe and my car is very loud which I don't want it to be. I am trying to go and get it welded shut at Golden Auto Muffler. Every time I shift gears you hear a lot of back fire. If I get my exhaust leak fixed from the welding job will this reduce the amount of back fire, will it get rid of the back fire pop or will it not do anything?

Please if you read this could you guys please comment?

Thank You