Unable to change GPIO values

[acef1]

I have a Pandaboard Rev A1 (OMAP 4430 processor) and I am trying to use the GPIO pins but having some trouble toggling them. I have tried doing the following:
$this->bbcode_second_pass_code('', '$cd /sys/class/gpio
$sudo su
$echo 140 > export
$cd gpio140
$cat direction
> in
$echo out > direction
$cat value
>0')

At this point, I used my multimeter to measure the voltage at the corresponding pin number 4 on the J3 expansion connector according to the reference manual. I got a reading of 1.80V, which I wasn't expecting since the value was set to 0. I then echoed 1 to the value and measured the voltage and it still read 1.80V.
I then tried another pin (number 10) to access GPIO_138 but still got the same behavior. Am I potentially missing some modules, or am I doing this entirely wrong? Eventually I want to use PWM to control some servos but I wanted to check if I can get basic GPIO functionality. Any help is greatly appreciated!