Well, I *guess* it's a knock anyway... The car has been sitting for a few weeks. It has been cranked twice in that time--once to move it and again a few days ago to help keep the battery alive. That time it was VERY hard to crank, probably due to the gas sitting too long.

I drove it today and it cranked fine but now makes noise. It's kind of hard to describe--I guess it's sort of a metallic rattling noise, almost like there is a loose object under the hood. It seems to be coming from near the drivers side dash. The rhythm and loudness are uneven. It's worse at idle and low speeds, and the idle RPM's also seem too high (1.5). Once I drove at 50+ mph I didn't really hear the noise anymore, but it was back when I slowed down again.

What could be wrong? Thanks!