rattling noise

Hello all!
 
I got a B200T which I really like (changed my '03 A190)...nice engine...smooooth yet powerful...silent as a shadow..... solid, as it should be...but..... keep hearing this rattling noise front left side....down near the wheel or between the wheels....I have thought may be the brakes..but not,,, those do not sound and I dont think they could rattle...maybe squeak...but not rattle (I am wrong on this?)......and I though it could be a panel, those big plastic panels that cover the "guts" of ther car that could be somewhat loose due a bump or something....but can not find the sourse... and is quite  disturbing well frankly ¡IS DRIVING ME NUTS¡¡  ----more nuts than before, I mean----
 
 
Any suggestions, plz????

I Got it¡¡¡ It was a plastic plate  covering the "guts" between front and reas wheels.....it was loose and  rattled al day long....Just to see if itr was the criminal, glued a wine bottle cork  to keep the plate in place but separated from the chasis and the sound is gone¡¡¡¡ now I will use some styrene foam to  bond the piece and will screw it together..... Im glad now the ride  comfort  is  much better