Using an inline spark plug tester to verify a plug is firing - P301 engine misfire error code

I install the inline spark plug tester between the spark plug wire and spark plug , then start the engine and show what you should see with a properly firing spark plug. I discuss the 'cylinder 1 misfire' P301 error code that is triggered when a spark pug isn't firing.
Using a code reader to find out why a ‘Check Engine’ light is activated :
• Using a code reader to...