How do you tell when a 1993chevy 305 coil is bad?

To determine if a 1993 Chevy 305 coil is bad, check for symptoms like engine misfires, rough idling, or difficulty starting. You can also test the coil with a multimeter; measure the primary and secondary resistance according to the specifications in the service manual. If the readings fall outside the specified range or if there is visible damage, the coil is likely faulty. Additionally, if you notice a weak or absent spark when testing with a spark tester, the coil may need replacement.