Small rattle sound when sx4 is idling.i have been told it's the bearings of a pulley, another diagnosis is starter motor. What is more likely. I have replaced the 2 small pulleys,

I caNt hear it either,
my guess its in the engine bay, you never said.
more likely, so you fix cars on statistics? that be expensive.
ever heard of a $5 stethoscope, sold in all stores,
so you can find the location
repeat that word 3 times, location, x3.
bad alt bearings, not guessing ,its just a list.
bad pS bearings.
bad water pump bearings
bad cam belt idler pulley, no engine stated, so? is it the GM 2L?

you do know you can drop bests for 3 min dead cold test right.
(not cam)
and last. any thing on engine loose can rattle."ANYTHING"
why not just get it fixed, your mach, knows how to find noises easy
also you can take a small rubber hose, to ear, and other end move all over the engine bay and sure can find noise location.
cost of tool 50cents.

I would need to hear the those.