I couldn't find anything in search for this??

At start up and start to drive away at about 5-10 miles per hour there is this vibrating sound and then goes away after 20+ miles per hour. Its under the car, not under the hood. I'm not sure if it's the heat shield or ???

Any ideas what it might be?? Everything is stock, car is 3 years old and about 29K miles.

 

Clutch clatter?

 

I have auto trans. Would that make a difference?

 

Short buzzing noise. Lasts just a second?

 

Yep. Search the tech forum.

 

It's probably your exhaust rubbing on something. Put the car on a lift, and look for any spots with shiny metal, or areas that should be dirty but aren't. If that doesn't work, then turn the car on and see if you can get a friend to replicate the sound while you're under the car.

 

It's your ABS & it's normal.

 

How neat is your car? It might ba a heat shield.

 

+1

It could be a number of things but since you're bone stock it will be easier to find.

 

ABS should not be causing vibrations at all times during idle and below 20 MPH. In fact, the only time you should notice ABS is when it kicks in, or when it pressurizes; which only happens very momentarily when the car is started.

 

That's my guess. Since OP didn't really say how long it lasted, it's hard to say for sure. Mine normally does it about 30 seconds after startup while I'm first driving away so the timing would be right - going 15-20 mph. Loud vibration.

 

My ABS isnt really a vibration, its more like just an odd sound followed by a woosh lol. Only when I first pull away @ about 5 mph, last about 1 second then its gone until the next time the car is turned on again.

I also think it's exhaust related, does the sound go away as the car heats up?
Low RPMs exhaust components/shield can rattle and then go away as you pick up speed/rpms.

 

Your ABS shouldn't be causing any vibration or making any sounds except for when you first start the car. when I read the OP, I assumed he's hearing the problem EVERY time he starts from a stop. As in, leaving a red light.

 

Maybe you have a bad yoke on the driveshaft?