- To judge the quality of coil according to spark color and distance.
- The car factory choose the appropriate coil depends on engine and ignition system.
- The normal spark distance is 1cm, and the spark shape is straight with violet blue color.
- The spark will be either red or curved, when the coil is aged or defective.
- The spark distance in air is much larger than the spark plug gap which is under compression and rich mixture in the combustion chamber.
- Spark Tester can adjust the spark distance to simulate the different types and conitions of ignition systems.