Can anyone help i brought a 2000 wrx bugeye and it came with the gfb blow off non adjustable full atmosphere vent duel port but its always been idling at 500low dosnt cut out seems to like it there and is alot quieter but ive tried everything to bring the idle up changed soark plugs cleaned throttle body cleaned mass sensor and no leaks that i can find and idle still stays at 500 even adjusted yhe idle screw that worked for a day then it want back to its home at 500 lol could it be the blow off valve? Not sure what to do next
Sounds like there’s a vacuum leak somewhere , it probably maybe the BOV is leaking. Only way to know is if your have a stock or another spare to throw on to test