Hi I have a 2009 buell lightening xb12scg I just got a few weeks back. It came with a jardine exhaust and I purchased buelltooth to diagnose the check engine light. The codes that come back are code 21 amc stuck open and sometimes it will run code 21 amc short to ground. I tinkered with it a bit and turned off the exhaust valve enable check box on ecm droid. When I do that the bike seems to idle normal and run properly. Last night I then found out my bike doesnt even have an air filter on it and lord knows how long the previous owner rode it without one.Could putting an air filter on be the final and last fix I need for it to run 100% and possible help to clear the codes that stick around even after tinkering with the exhaust config on ecm droid, because simply checking exhaust valve enable doesnt exactly clear the codes from ecm droid, but it does flick off the cel. When I manually erase the codes on ecm droid, the bike starts to sputter and idle like it wants to shut off, but when I leave the codes in the "stored errors" section and not randomly erase them, the bike runs fine and doesnt putter.