If you mean while the car is standing still, that's due to a cylinder misfire. The most common suspects are the spark plugs and wires. If you mean while the brakes are applied and the car is slowing down, that's due to warped brake rotors. They can be machined for that as long as they will still be above the minimum published legal thickness, otherwise they are replaced.
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Tuesday, April 9th, 2013 AT 9:11 AM