I've got 90k miles on this thing.  I've developed a metallic clicking sound on my front left wheel area that only happens when I brake, decelerate or turn right (I haven't heard it happen when I turn left, but I won't say it doesn't do it).  It doesn't pull and the brakes work fine.   My research originally said that the nut holding the wheel on probably came loose, so I tried to tighten it and it wouldn't budge so I'm pretty sure that's not it.

I checked and replaced the brake pads and no change.  While the wheel was off, I did an inspection of the assembly and the only thing that caught my eye was a build up of gunk around where the brake line that comes from the master cylinder enters the caliper assembly.  The brake fluid was not low and again.. no braking problems.  This has gone on for a little over a year and I think it may be getting a little louder.

I'm at a loss as to what to check next.   Any suggestions?

Thanks,

Tim.