[ap5512]

^^ I don't think you should worry if you had yours installed by a pro. This was my first time installing a header. It wasn't difficult but I could tell right away something was wrong. The sound and smell was very apparent.

I installed the header last week and noticed the sound getting obvious on cold starts and every time i was on the gas pedal. I'm just really glad I took the time out today to inspect them. I think had I waited a few more days, the very loose bolt would have flown away.

Once I re-tightned to torque spec the sound was instantaneously changed and it sounded the way I expected. The way I see you shouldn't be hearing any type of strange fluttering sound on starts/accelerating from the front of the car.