Im trying to adjust it to make sure it stays closed at WOT. If I add the washers to it, it doesnt open at idle.. But if I leave the washers out it seems to work fine but I think its leaking at WOT.. Is there anyway to tell??

 

Well your either going to have to run REAL fast, or check it on a dyno at WOT.

Another way would be to check the valve with a mityVac that does pressure or a regulator off an air compressor. Put 7 psi or whatever your running on the valve and check if it's shut.