Metal on Metal Noise

My 2009 Accord is making a metal on metal noise when I drive. It’s not all the time, probably about 1/3 of the time or so, and only when I’m accelerating/cruising, not braking. It’s very loud, and when I took it to a mechanic they just took it for a ride, didn’t hear anything, and told me to come back when it’s more consistent. Any ideas what it could be? I’m nervous even taking it out now.

Can you tell where the noise is coming from?

It seems to be coming from the drivers side, probably the wheel area, but I can’t rule out under the hood. But it seems to be closer to the wheel area.

Um, front, back, coasting, accelerating, slowing, turning left right, braking, smooth road, rough road, etc. Details, details my friend.

Front wheel area (although I can’t rule out under the hood), coasting/accelerating, doesn’t seem to be related to turning or road conditions at all. It’ll start as I accelerate from a stop, continue as I’m driving, and then as I stop it’ll grow quieter until it ceases as I come to a stop. It’s a very high pitched, loud metallic/scraping noise. I’ve looked around and can’t find anything noticeable.

The noise might be coming from a brake pad wear indicator.

Look at the pad on the lower right. https://www.rockauto.com/en/moreinfo.php?pk=3538680&cc=1443202&jsn=353

These are metal tabs that are designed to come in contact with the brake rotor when the brake pads become worn and make noise.

I would suggest that you have a brake inspection performed.

Tester

My prime suspect would be the audible wear indicators, telling you that you need to replace brake pads imminently. Yes, I know that the OP stated that his mechanic didn’t hear anything, but some mechanics experience a degree of hearing loss over the years as a result of their jobs.

Because brakes are not something to take any chances with, I strongly urge the OP to have a mechanic examine the condition/depth of the brake pads a.s.a.p.

I vote brake pads too. My wife has to remind me when they start to squeak. I don’t hear a thing. Too many shot gun shells or dances or something.