If i were you i would put all the stock **** back on the car and run it like that.. The car is giving you a lot of trouble. Enjoy it longer by converting it back to stock, until u can get the block inspected and rebuild.. Putting all these mods on is just straining the poor car. Previous owner beat the **** out the car and it cannot handle anymore abuse for much longer. Im telling you. You should have never purchased a modified car. Subaru's are fragile machines. Get that engine out and rebuild it ASAP bro!