Go back to the beginning,forget the coil check the fuel pump is connected the right way round,it may have arrows on it showing the direction of fuel flow,also make sure electrical connections are tight,if it is fastened with jubilly clips are they airtight,you may be drawing air in to the system,your problem started on changing the filter it is a fuel problem.DONT go chasing other possibles you you will be on forever and wasting your time,SLOWLY,SLOWLY go back and rechek the filter fitting job and try again,also check if the fuse hasn't blown for the motor they can get a bit of a shock when disturbed.
Rich, December 2007