I have a 1990 Volvo 740 wagon with a quarter million miles that I've had a bunch of stuff done to: New transmission, new alternator, new brakes, etc... Last year I had a new exhaust system put in after the old one literally fell out. It was great until after this insane winter. Now it's noisier than it was and it makes a metallic rattling sound when the car is first started and sporadically when driving or idling. The shop that put in the new alternator suggested I have the heat shield removed and that it would cost a few hundred bucks to do it. I didn't like that advice and figured I'd try to figure out if there was another way. In the following photo I'm touching a piece of metal that moves around enough when you touch it that it makes a metal-on-metal sound. Could this thing be the culprit of the rattling? Is it the heat shield? What should I do?

http://i111.photobucket.com/albums/n...g/Image147.jpg

 

That looks like the remnants of the hot air exchanger. Originally, there was a top piece that had a ~2" diameter nipple that flexible metal ducting ran up to the bottom of the air box. Helped the car run better sooner in cold weather. Really serves no purpose. If that's the heat shield they are referencing I think they are scamming you. Ten minutes with a chatter gun or 5 minutes w/ a torch or 2 w/ a hammer and it's gone!!