How do you test the ignition coil on your 91 geo storm?

To test the ignition coil on a 1991 Geo Storm, first ensure the engine is off and disconnect the negative battery terminal. Use a multimeter to measure the resistance across the primary terminals (usually around 0.5 to 1.5 ohms) and secondary terminals (typically 6,000 to 12,000 ohms). If the resistance values are outside these ranges, the coil may be faulty. Finally, reassemble everything and reconnect the battery to check for proper engine operation.