Spark Plug Tester

The automotive ignition system is composed of power supply (battery or generator), ignition coil, distributor, spark plug, ignition switch and control circuit.

Working principle of automotive ignition system
In order to work properly, the ignition type engine in accordance with the ignition sequence of each cylinder, regularly supplies the spark plug with high-voltage electricity (about 15000 ~ 30000V) full of high-energy. So that the spark plugs generate strong enough spark to ignite the combustible mixture.

Normally, the requirements of car ignition system are as follows:

1. The spark must have a sufficiently high breakdown voltage.
2. The spark must have high enough energy to ensure reliable ignition.
3. The ignition timing must be able to adapt to changes in engine operating conditions.

Due to the large number of ignition system components and the working conditions are often harsher. After using for a long time, the performance of ignition system will decrease, and failures may occur, which will affect the power and economy of the engine. In severe cases, the engine will stall or fail to start. Therefore, the failure of the ignition system is one of the important reasons why the engine cannot work normally.

In order to ensure the normal operation of the ignition system, when the performance of the ignition system is degraded, we can immediately check it in detail.

For the detachable ignition system, we can use the substitution method to test each part of the ignition system separately.

For example:

• Use an in-line spark tester to simulate the working condition of a spark plug, skip the car spark plug and directly connect to the ignition coil to finish detection. If there is a problem in ignition coil, the tester will indicate on its panel.
• The spark plug can be disassembled and placed in a spark plug tester for inspection. The spark plug tester can simulate different vehicle speed mode to judge the performance of the spark plug.
• For other control circuits, a good method is to use an oscilloscope to directly check the ignition system. Analyze the primary and secondary voltage waveforms of the ignition coil (mainly the secondary voltage waveform), test the ignition advance angle, and then judge the working condition of the ignition system.