It's possible there's a recall that needs to be done on your vehicle that relates to the issue you're having. Call your local Hyundai dealer with your VIN and ask them to check for open recalls. If recall 039 is open, take the car in for the recall to be done.
Dealers in Northern Virginia are Alexandria, Brown's (Manassas), Fairfax, and I believe another in Woodbridge whose name I cannot recall. The closest dealers across the bridge are Fitzgerald (Rockville) and Pohanka (Marlow Heights).
If the recall has already been done, register for a free account at
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and check campaign bulletin 00-01-005. To the best of your ability verify the campaign has been done properly.
If the campaign has been done properly, you probably need a new air flow sensor. If you want to try this, it's simple enough to install. Just make sure the arrow indicating air flow direction points toward the throttle body.
The fact that the lamp went off means that there were three consecutive drive cycles when the issue wasn't present. As far as the computer is concerned, it's fixed for now.
I don't know of any places other than dealers that are good with driveability issues like yours. That doesn't mean they don't exist, just that I don't know about them.