How do you know if your coil is bad on a 1998 Volvo S70?

To determine if the ignition coil on your 1998 Volvo S70 is bad, look for symptoms such as rough idling, misfiring, reduced power, or difficulty starting the engine. You can also perform a diagnostic test with an OBD-II scanner to check for related trouble codes. Additionally, visually inspect the coil for any signs of damage, such as cracks or corrosion. Testing the coil's resistance with a multimeter can also help confirm its functionality.