Check the bolts holding the IP on,.. especially the bolts holding the bracket to the block, behind the pump.
an el-cheapo fuel filter can possibly do this, use a good one its your 'life line' that and air filter
The 3 bolts holding the serpentine belt setup to the 1.6d block all had snapped. Im guessing the bolts somehow worked themselves loose and were causing the alternator bracket to to rock back and forth causing the bucking sensation at low speeds.