noisy idle

My car sounds a little off; there is a rattling, higher-pitched note in the exhaust that is most noticeable at idle. I tightened up the exhaust (it was getting a little loose) but the noise is still there. I'm adjusting the valves tomorrow, is there anything else I should try?

Did you check to see if your fan is scraping against the shroud?
Try pushing the shroud back a little to see if the noise stops.
Just a thought......

I did read about that; my fan shroud seems really sturdy. Couldn't budge it. The sound seems to be in between the exhaust notes, if that makes any sense.

Get the car up , preferably on a rack, with a cold engine..... When the engine is started,, quickly run your hand around each exhaust flange to head connection to check for leaks...Obviously, this must be done quickly.....If you feel any blow by, check the connection with a mirror and light, or anything else that will work, to see if it's a cracked weld or pipe....Don't go overboard trying to tighten up the flange....Gently does it....

This has happened to me two times with my last header system....I have since replaced it....

When adjusting valves - retorque the heads. A very loose nut indicates a stud pulling out of the soft alloy engine block. Might do a quick compression check too. If exhast was loose and had gaskets (steel/asbestous-like) - it is possible it blew out some of the sealing gasket - so tightening doesn't help much.

I don't think it's the exhaust, it's more of a rattle and it doesn't go up and down with the RPMs.

Loose tin, attachment, or standing to close to the Lacquer thinner....;-)

Stephan:

My exhaust system rattles like hell whenever it's cold, and the noise is coming from the slide-tubes (those tubes that go across the back before they enter the collector and have to slide back and forth a little bit as the engine heats and cools.

I hesitate to put clamps on them, as they're supposed to move a little, so I just live with the rattle (it usually goes away when hot). It has a melodic note to it - not just a rattle, but a faint ringing with it.

Sound like what you've got? If you want to play around, get a pair of those brown work gloves and pull them on, then pull on a pair of leather work gloves over them and then, with the engine running, carefully (don't get caught in anything moving) grab the intersection of the slide tubes and hold them fast. If that's the problem, the rattle should go away. If not, it's elsewhere (but you'll now have a pair of heat-polished leather gloves).

gn

I don't have any slider tubes, I don't think.

Can you post a picture?

Did you check the fan nut? I was going to a show just up the street last fall and noticed a funny rattle at idle. When I got to the show (fortunately only about a mile) I checked the fan nut just on a hunch. It wasn't even finger tight. I torqued it back down with some thread locker and that solved the problem.