It isn't the vehicle you purchased, it "Welcome to HF Mobile". Are you sure it's hash? Bob Lewis, AA4PB, gave you the right answer if it is, although it could be the IAC (idle air controller). I suspect it's ignition noise. There is a lot you can do.
On my web site, http://www.k0bg.com
, I have links to all of my articles I've written for eham.net about noise abatement in HF mobiles. I've expanded on some of them and they are posted on the site.
Incidentally, the Hyundai uses Mitsu and Denso electronics, and they're both some of the better designed automotive hardware out there.