I have an 87 ford ranger with a 2.3 full injected, 4 cilinder motor in it. when I'm driving it the idle gets so high that no matter what I do I can not get it down

 

Grab the butterfly shaft on the throttle body and see if you can wiggle it up and down or side to side.
If you can then the throttle body is worn and is either causing the throttle plates to stick , or allowing a vacuum leak.