DC Motor driver using MOSFET(IRFZ44N)
Hmmmm. A gate voltage of 3.17V might not be enough to close the drain-to-source channel. Best option might be to use a buffer cause you should be getting an output closer to 5V. 3.17V  might be due to your supply can't source large current. I won't suspect much that is because of the FET because it has high impedance. Try removing the pull-down resistor (1 Meg) and measure again the gate voltage.. It should lessen the current drawn.