Ok so my car has been acting a little weird latley ! I have an 07 wrx stage 2 with a catless 3'' exhaust. When i go WOT in first i get around 10 psi 2nd and third i get a good 16.3 to 16.9 but at 4500 rpm it starts to plumet and finishs at around 13 psi at 6100. In 4th or 5th gear I often get to 18 psi and then the check engine light appears with the p0244 code ' Tubro/wastegate Solenoid A '!! But when that doesnt happen I'm still boosting 17+ psi and at 4500 rpm it goes down to roughly 14.5 psi! Whats wrong with it ??