Well I removed the BOV line which made this happen. Knowing there are quite a few hoses that will produce the same effect including the gas cap it will take same time finding which hose is leaking. Don't forget the lines under your intake manifold heading to the Emission system. Hope this helps, good luck.

 

Had an issue with my cams/idle sounding really lumpy. I was tuned and had HKS 272/272 and didn't think much of it until i installed a AEM Wideband A/F gauge. Found out i was running lean at idle (16-17) and rich at WOT (10 and below). Replaced my coil packs with a Spoolin-Up COP setup and lumpy idle went away. Check your coil packs/spark plugs if you drive a higher mileage Evo.