scoobwrx94import

arite folks am newbie here right i have a 94 wrx import and got it while back with suspect headgasket engine was running mint really quiet could only tell headgasket was gone after went over about 4 thousand revs ie wen on boost temperature gauge would creep rite up to the red but if i backed of would creep back down again

anyway took it apart replaced all belts and gaskets with genuine subaru parts from town and county in aberdeen then had it running and was tickin like *** for a while then went quiet again just back to what it was before i took it apart it has been sittin in my lockup while i do it up and have started it couple of times to take it out garage and now it has started tappin like *** its coming from the right hand side where the oil cap is anyone tell me what it is or why its happening doin my head in