After breaking the seal & tearing apart the Idle Speed Regulator, I discovered what the cause of the motor failure was. The motor had not seized in the sense that it had locked up permanently, but was stuck in place. At the end of the spindle shaft down in the chamber, there is a metal piece on the end that rotates around. At the bottom of this piece is a metal rod that sticks down. On the bottom of the chamber itself is a nitch that takes up a quarter of the space. What had happened was the entire center assembly slid down, and the rod on the end had slipped into the nitch. When power was applied the spindle would turn as normal, but would then stop as soon as the rod hit the end of the nitch. Now that I know the cause, my original question remains, but I have a new one; Does the Idle Speed Regulator Motor pump air into the engine, or does it limit the amount of air that goes into the engine to create an "ideal" idle (the same sense that the LAMBDA system works)? Right now I have the motor back in place with the chamber about ¾ of the way open, and the engine is idling at 1500 rpms. I'll try working with it to see about getting the idle down to at least 900. Either way, the unit is destoyed so I'll need another. -Robert vin 6585