Rattle in side in Broan 502/503 discharge fan

SOURCE: Rattleing noise when either oven is turned on

It could be a loose screw that has fallen from inside your back panel.... Be sure to turn off all power sorces before you access the panel to avoid electrical shock!

SOURCE: diamater of downrod

the fan must be tight fit to downrod.

SOURCE: Damper need for Broan Range Hood

I called tech support at Broan and was told they recommend two dampers in cold climates ...one at in the wall cap and one on the unit. They make the damper,
(#BP87-7"), that attaches to the round duct plate that comes with the hood. Strangely the unit does not include a round damper and the seller LOWES did not have it, also checked Home Depot,.
The Tech said they can't get stores to stock it. I checked at a local supplier of all kinds of plumbing, heating, and cooling supplies and they only had basic 7" dampers which, I was told would probably be too heavy, and be manual. I ordered it through Amazon/True Value ($11.56 w/ shipping, shipping more than cost of damper). Tech indicated that the 2nd (unit damper) is optional and may not be needed if in a warm climate. I would suggest that Broan include the $5.00 item in their unit or at least sellers stock it.

SOURCE: 98 Corolla Rattling

timing chain tensioners are commen on the 1zzfe. the tensioner is about $50 and the labour another .5 hours.

SOURCE: Every time the compressor comes on something starts to rattle loudly in the housing. I can stop the rattle by pressing down on the sleeve but this is not a practical solution. Any suggestions?

Something is obviously loose. It may be the fan. See this diagnostic article on this topic:
http://yourhandymanzone.com/Your_Handyman_Zone_How_To_Pages_Home_Improvement_Zone_Cooling_Ventilation_Systems_Central_Air_Conditioning_Making_Rattling_Sound.htm

Hope this helps.
Brad