What are the main faults of the ignition system?

The ignition system of ordinary automobile engines mostly adopts contactless ignition system, and the main faults of the ignition system are as follows:

1, spark plug failure

Fault symptoms: carbon deposit, oil pollution and overheating of spark plug.

Cause of failure: carbon deposit on spark plug: the end of insulator, electrode and spark plug shell are often covered with a thick layer of black-gray powder soft scale. Spark plug oil pollution: failure phenomenon: the end of insulator, electrode and spark plug shell are covered with a layer of oil. Spark plug overheating: the center electrode melts, the top of insulator is loose and soft, and the end of insulator is mostly gray and hard.

2. The ignition is too late

Fault symptoms: muffler is loud, carburetor backfires quickly, engine coolant temperature is high, and the car is weak.

Cause of failure: The ignition angle is incorrect, so the ignition angle can be adjusted to the specified value.

3. The ignition time is too early

Fault phenomenon: unstable idle running, easy to turn off; When accelerating, the engine has a serious knocking sound.

Cause of failure: The failure is mainly caused by adjustment of ignition timing or misalignment of ignition angle assembly. You can connect the ignition detector and adjust the ignition advance angle to the specified value.

Extended data:

Maintenance method of automobile ignition system;

1, check the appearance of ignition coil regularly, keep the appearance clean, and the inside should be moisture-proof to maintain its good insulation performance;

2. Check the connection between the high-voltage lead-out screw of the ignition coil and the high-voltage line to ensure that it is firm and reliable. If the connection is loose, it is easy to cause discharge flashover, which will lead to the burning of the connection parts and cause potential safety hazards;

3. Prevent the high-voltage wire and spark plug cap from loosening. One end of the secondary winding of the ignition coil is connected with the spark plug through the high voltage line and the spark plug cap. When the high voltage line or spark plug cap falls off, the high voltage generated by the secondary winding will rise to the limit value determined by the working capacity, which will easily lead to the breakdown and damage of the secondary winding.

4. Ensure that the primary winding of the ignition coil is firmly connected with the external circuit. In the battery ignition system, the connection between the low-voltage terminal and the external circuit usually has polarity regulation, that is, the low-voltage wiring of the positive electrode should be directly or indirectly connected with the positive electrode of the battery, and the low-voltage terminal of the negative electrode should be connected with the negative electrode of the battery.

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