Proper installation for coil-on-plug boots

Coil-on-plug (COP) boots connect the ignition coil to the spark plug, ensuring a reliable and efficient transfer of electrical energy. However, many people cannot determine which end connects to the spark plug and which end connects to the coil.

The narrow, more tapered end is designed to fit snugly onto the spark plug's terminal, while the wider end or base connects to the ignition coil.

Forcing a COP boot onto the wrong component can damage both the boot and the ignition system, leading to issues such as electrical shorts, misfires, or poor performance. Proper installation is crucial to avoid these problems and ensure reliable engine operation.