If you are standing at the front of your car looking at the engine it is on your left. twards the back. It screws into the Plenum, is an electrical device and has wires comming out the back of it. If you look it up it is a GM part and I think the astro vans used the same part . search D-90...Suppose to help with idle and not stalling when going slow. Link from rovers North. http://www.roversnorth.com/store/p-3630-stepper-motor-efi-v-8.aspx
Hope that helps. I always got hung up looking for an actual motor.