2004 subaru wrx wagon. So i have this hesitation problem in the higher gears, 3rd 4th and 5th. its under heavier acceleration. starts about 3000 rpm and continues through the gear. i have cleaned the MAF. the dealership "replaced" the throttle position sensor/connector. i have replaced the neutral safety switch. I am still getting this problem even with a cobb stage 2 tune running 91 octane. i do have invidia catless downpipe and invidia catback exhaust. stock intake. i would like some opinions and hopefully someone who has had this happen before give me advise. Thanks.