If you are the average motorist, you probably think that all spark plug wires are the same and that you and just yank out the old resistance ones and pop on the new non-resistance ones and you are good to go. But you would be wrong. Oh, so wrong. Here's why. Many modern ignition systems that were designed with the resistance as part of the circuit. You use non-resistance wires and who knows what kind of damage will result. So here's the rule: Always use replacement wires that were designed for your vehicle's ignition system.