Try to locate the rattling noise. I would especially check the catalytic converters if the noise sounds like it is coming from underneath the vehicle. Usually throughout some time the honeycomb material inside them will break up from 'heat stress' and will rattle around there. In some cases it can get lodged int he pipe between the converter and the muffler blocking some of the path of the exhaust causing some major performance issues.
When it starts leaking are making noise.
bad wheel bearing may cause it
YES it is. GM had a problem with the fuel pumps making noise and still does.
loud rattling noise when idling.
Depends on where the noise is whats making the noise. Can you be more descriptive of where and what?
if it's a turbo check the turbo
Without further information this question cannot be answered
check the exhaust line one of the heat shield (metal plate between the pipe and the cab) migth be loose
My 1997 Honda CRV is making a rattling noise when driving in rough roads
Check to heat-shield at the catalytic converter because something is loose
Inspect the catalytic converter heat shield.
The rattling noise is in there so you can move the head around.