J0el07

So I recently saw a thread, DIY BOV, and I gave it a try. I removed the recirculating tube/hose from my 2008 535i ....and plugged up the whole on the intake pipe. So now the DV releases to the atmosphere instead of recirculating into the intake. I really just did it because I like the sound it makes. While I was doing this I noticed a bunch of build up on one of the DVs.....is there a way for me to test if this DV is leaking....?

Also, I know now that I have made the DVs release to the atmosphere, I know that my fuel to air ratio will be off. Will it make that big of a difference? If so, is that a flash I can install that will correct this? I also have JB4 currently installed.