Smooth Installation: First, turn off the engine and remove the spark plug coil. Start the engine. If the ignition coil is in good condition, the tester's indicator light will flash, indicating the ignition system's operational status.
Osilly Car Inline Spark Plug Tester, Automotive Engine Ignition 2 PCS
Car Inline Spark Plug Tester Vehicles Straight Boot Engine Ignition Coil Tester
