Originally Posted by The Lad
Well, it's first service (in my possession) was about 4 months ago. They replaced the air filter at the time, and in fact I installed a replacement K&N (E-2022) filter last month and this thing still shows up every now and then. The actual intake hasn't been looked at though, no, but I understand your thought process.
Strange thing is, that "suction" noise seems to be coming from underneath the car - which could be related to the exhaust somehow - but I'm not sure
It's probably not the intake then.
The sound coming from underneath could just be resonating so it's hard to pinpoint it unless you can open the hood and have someone look in while you rev? Not sure if it only happens while driving but if revving can reproduce that sound, I recommend doing that.
It could be so many things, but it definitely sounds like an air leak. It could honestly be some tubing to your BPV, which can explain all the symptoms. But you'd probably be stalling out as well.