New Brake Noise
 

I recently got my car back from the body shop. It sat in their lot for three weeks while they waited for parts to come in. Now the brakes make a subtle noise and pulse. I don't think the work required the removal of wheels., although they may have removed the rear wheels for easier access. I'm familiar with the sound of a little morning rust, but I can feel this pulsing in the brake pedal.

What type of body work?

Check the brake rotors for rust.

Pulsing is indicative of warped rotors. I would ask the body shop what they actually took apart to ascertain better. Three weeks is a long time and maybe some rust has bound up some stuff? Brake hardware might need rust cleaned off and new lube on contact points.
How many miles have you driven it since getting it back? It might just need to stretch it's legs.

Hmm, think I found the problem. Luckily this black crud comes off with brakeleen and a plastic scouring pad.
https://cimg1.ibsrv.net/gimg/www.cam...f644c6636f.jpg

Did cleaning solve the issue?

A little, but the back crud is just brake pad material packing into the corroded areas. I've never seen rotors get pitted by rust like this before.

Wow, it really did sit for quite some time.
How many miles have you put since getting it back? I wonder if a couple of hundred miles might burn that off.

Maybe a hundred. I think semi-metallic pads would burn it off better than the ceramics I have.

You're probably right. Good luck!