Yes, it's actually really easy. The TPS sensor is pretty much a potentiometer. Testing it, you want to use the ground at the plug. Sneak the meter leads along the wire into the back of the plug. Best to use an analog meter for best results.
3 wires; one is constant 5 volts, one is ground, and the other is the signal to the computer (test with key on engine off). The voltage increases as accelerator is applied.
What you want to watch for is how the meter sweeps with the throttle body - any dead spots indicates a bad sensor and the analog meter should sweep smoothly with the TPS sensor. You will have to remove the shroud over the throttle cable to access the throttle lever. Typically you see around .98 volts at idle, and high 4.xx at WOT.
Don't mess with the TB screw!
That is not a manual idle, but it sets the base voltage for the TPS sensor. The computer controls the idle speed.
This site has a lot of info that can help you test sensors and diagnose problems - link to the TPS section: