my '03 Caravan has had an engine rattle for quite some time now. only hear it at idle. Has the 3.3 litre Flex fuel engine. so I took the serpentine belt off and ran it and did not hear the noise. I hand-turned each pulley and only the power steering pump may have had a little play in it. However when I put the belt back on there was no noise for about 3 hrs driving and then the noise re-appeared. any help is appreciated

 

Use a stethescope or a piece of hose and listen to each item driven by the belt. Be very careful and do not get tangled with the belt.

 

thanks papaduck, can I rule out the timing chain since the noise went away temporarily?