It could be a number of things, really need to listen to it as it goes through it's firing sequence.
Can you hear it sparking, if not could be the transformer. Could be a split electrode lead shorting.
Have you tested the solenoid?
Is the oil pressure and air setting correct.
Does the motor buzz when it's started, could be the capacitor or the motor.
Have you tried a second control box? Just because tghe new one is straight out of the box doen't mean that its 100%
SDG26100
January 2011