When I got home tonight there was a strange sound coming from the engine, sort of a boiling sound. I guessed from the radiator, it makes sense why it would make this sound. what worries me is it has never made that sound before. it was like boiling, much higher pitch and very rapid. i am somewhat worried that something may be broken. if anyone could advise me as to why it suddenly started doing this, i would appreciate it. thanks!!

 

Check ur antifreeze, my friend had the same problem on a GS400 and it was low on antifreeze.