[talonite]

you really need to take like 5 steps back and slow down. instead of just throwing parts at it and wasting your money do some research and figure out what cause idle surge or (idle hunt) it has been said before there is alot of info on here and a few other sites. do a proper boost leak test and do it in detail, if nothing then look at some of the causes of idle surge. You have the IAC, tps and i think there are a few others. And as for the barometric pressure code that is probably an air leak. as for the tranny if its slipping, possibly the end of it. But I wish you good luck, and hopefully you have some fun doing all this.