My 93 245 has always had a rattling plastic sound over bumps and start up since I got it last summer.I thought it might be a loose strut part or similiar.Looking thru the previous owner repair bills (all dealer work) The owner complained about "a plastic rattling sound behind the center console" only 9 months after they bought it new in 94...The dealer dismissed it as "coins in the ashtray".So this sound or loose part has been doing this for 14yrs!!I have a bad heater control valve and once I poked around under there to see how hard it would be to replace the valve.I saw no loose parts that would rattle,now I am wondering what part could remain loose shaking and rattling for 14 yrs,apparently with no ill effects,except for the aggravating sound???

when I replaced the heater core on my '90 245 noticed a lot of relays that were not anchored to anything. It is possible that it is one of these. If you want you could remove the glove box and get a better look. It may also help to remove the speaker grill on top of the dashboard as well to get more light in there.