Had my scion xb for a year , havent done aything to the engine but just recently , when the engines at idle it makes this rattling noise like the hoods lose (but its not) only does it sometimes and only at idle. Oil isnt due for another 1k so Anybody know what it could be ?[/b]

 

yep, i had the same problem with my tC and i checked every single thing. and finally i found it. the radiator is loose. tighten up the bolts on the top and the problem should go away. let me know if it still rattles

 

Does the rattle also happen at stoplights? If so, your hood bumps (4-black cylinder things) in your engine bay may need some adjustment. The factory folks may have tightened for shipment from Japan to US port.

 

Checked all the radiator bolts and hood bumps and their all tight, I did notice that the sound only comes when the trans is in drive and idleing (stopped) . but the engine runs fine its just annoying.

 

same issue all my tv's inside rattle and if i put my auto in neutral it stops and quiet idle other than that it vibrates like i have a busted motor mount. But cant be its only a yr old help!

 

figured out , its the hood bumpers turn them counter clockwise until the hood closes snug