It's a car metaphor. You've got your foot pressed on the accelerator right down to the metal floor board. It's a symbolic way of saying, you're going as hard and as fast as you can.
1. Porsche and Ferrari owners will put their peddle to the meddle peddle to the metal if no firm speed control measures are built-in

2. I'm into music that make me want to put the peddle to the meddle peddle to the metal on the highway.

3. Crack the steel, peddle to the meddle peddle to the metal, mash the gas and mash the wheel
by Paoloit January 15, 2009
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