How do I check for faulty spark plugs? CAN THIS WORK?

There is one other answer to your question to see if you get spark to the plugs and that is if you just hold the spark plug wires while someone turns over the engine to see if it has spark and your eyes light up everyone will know that you have spark to the plugs.Its only if you want all that electrical power going through you to ground when the engine turns over for testing.