WordNet (r) 3.0 (2006):

fits and starts
    n 1: repeated bursts of activity; "they worked in fits and
         starts"

Moby Thesaurus II by Grady Ward, 1.0:

55 Moby Thesaurus words for "fits and starts":
   ague, arrhythmia, brokenness, bumpiness, capriciousness,
   chattering, choppiness, chorea, cold shivers, desultoriness,
   disconnectedness, discontinuity, eccentricity, erraticness,
   fibrillation, fitfulness, fluctuation, inconstancy, intermittence,
   irregularity, jactation, jactitation, jerkiness, joltiness,
   nonuniformity, palsy, patchiness, quaking, quavering, quivering,
   roughness, shakes, shaking, shivering, shivers, shuddering, spasms,
   spasticity, sporadicity, sporadicness, spottiness, stagger,
   succussion, trembling, tremulousness, uncertainty, unevenness,
   unmethodicalness, unpredictability, unsteadiness, unsystematicness,
   variability, vibration, whimsicality, wobble