Top 3 Biggest Sources of Grief from Your Knitting Machine

The sponge bar is too old: Remove the sponge bar from your machine and leave it overnight. If the sponge does not puff up, or has separated into two parts, or is oily, replace it.
Bent needles: Push all needles out to hold position. Carefully, look for needles leaning towards it’s neighbor. That’s a bent needle. Replace it. Throw away the old needle. ALSO the tail of the needle may be bent if it doesn’t return to rest position smoothly. Replace it.
Oil: clean the old oil from the rails the carriage slides on and the surfaces of the bed and underside of the carriages removing lint as you go. Re-oil using knitting machine oil following the instructions in your manual. Do not use any other oil than knitting machine oil.