odd sound when the car starts

[micjordan]

I am noticing a strange sound when starting my 1993 740i but today I heard it very well because i was in a cement parking garage and the sound was enclosed in the area rather than when starting it in my driveway. All I can say about it is that it sounds exactly like a ball bearing being thrown at the inside of a tin can. It only makes this sound once just as the engine is starting up and never again while the engine has started (that I can hear). From what I can hear it sounds like it is coming from underneath the center of the car area rather than the engine area but I could be wrong as I'm in the car when I hear it. Any ideas?

[winfred]

posible busted cat, possible a header inner shield is coming apart (they are double walled, i've seen it happen)

I am noticing a strange sound when starting my 1993 740i but today I heard it very well because i was in a cement parking garage and the sound was enclosed in the area rather than when starting it in my driveway. All I can say about it is that it sounds exactly like a ball bearing being thrown at the inside of a tin can. It only makes this sound once just as the engine is starting up and never again while the engine has started (that I can hear). From what I can hear it sounds like it is coming from underneath the center of the car area rather than the engine area but I could be wrong as I'm in the car when I hear it. Any ideas?

[micjordan]

jesus christ....$6000 and counting

[micjordan]

Hmm...could this be related to a louder than normal exhaust sound? I just realized I've been noticing that but thought I was imagining things until you mentioned the cat