car starts most of the time but on 1997 Pontiac Grand Prix GTP

occasionally there is nothing when you turn the key. If I turn the fanbelt just a little, it will start. The crank position sensor was changed with original part about 6 months ago.

3 answers 2 comments
Missing some information?? "turn the fanbelt just a little"? Sounds like a stripped spot on the flywheel. Is the starter sometimes making noise , but not spinning the motor?
Starter drive engages flywheel but does not turn, stays ingaged, turn engine by belt turns armature and disengages drive, next cycle starts engine. That's my guess anyway. Dead spot on armature, should hear it click one time though.
MERRY CHRISTMAS! Hope i get some green jelly.
>>>>>>.........:)..U2
Replace the starter.
possible ignition switch...