More or less the same problem you have.

MICHAEL, let me introduce myself, my name is Miguel, I live in Spain and I have a 4runner of 95, nice truck. Since the last summer I´m experiencing something simmilar to you (I think). For instance, driving to 100-120 Km/h for a while, if I let the gear in neutral and loose the accelerator to idle, the engine stops in few seconds, of course, moving the entire car. Also, if a push hard to engine quickly for get the next gear and release the pedal, the engine do the same. By other hand, i felt some loose in the power of the engine. Next monday (29/Nov/04) I will left the car in a Bosch Injection Service, it seems is a problem with some sprigns in the "idle control" INSIDE of the injection pump (expensive repair !!!).

I'll keep you in touch, pray with me for the cost of the repair.

Regards.
Miguel