06 wrx. Freeway speeds 65+ in 5th gear. When I floor it the boost bounces up and down 4 psi, give or take. Only happens on stock map, fine when on stage 2 with AP2. Any thoughts???

 

the stock map only boost 10 to 13 psi give or take if u have no cat the car is run lien that is sometime the reson. if u have stage 2 map the a/f rito is different then stock

i have header downpipe cat back all after markt have not get protune yet but soon .i have the same problem before i boght the cobb ap

dnyo i was runing 205 hp and 265 tq awp

 

Seems like car runs rich in all maps, even though I am catless. I guess i'll wait until i'm done with add ons and then get pro tuned.