Not too familiar with the wire colors on the Sr's. but if you have ignition on, and you put one lead on a good ground, and the other one back probed into TPS connector one of the readings should vary its reading with the throttlebody changing positions. If not...you're either not doing it right, or your TPS is bad...they're a dime a dozen man. just try to replace it. Have you tried to take it off and just inspect the potentiometer yet?