running funny

[rb-4-mee]

ok i just did my rb swap the car ran fine for like 2 months i had hooked up my boost gage it read the vacume at 20 and the boost at 10 now it reads vacume at 10 and wont let me boost up past 5 pounds add feals like fuel cut iv replaiced my maf,tps,,plugs,coils,and plaid with the timming what els could it be