How to Distinguish Between Good and Bad Spark Plugs?

[LeSteven]

Methods to determine the quality of spark plugs: 1. Spark Test: Remove the spark plug and test it on the cylinder block with a high-voltage wire. If there is no spark or the spark is weak, it indicates that the spark plug is leaking electricity or not working. 2. Color Observation: Remove the spark plug. If the surface appears reddish-brown or rust-colored, it indicates the spark plug is normal; if it is oily, it indicates a gap misalignment, excessive fuel supply, a short circuit in the high-voltage wire, or non-operation; if the spark plug is severely eroded, with phenomena such as blistering at the top, black streaks, cracks, or electrode melting, it means the spark plug is damaged and must be replaced immediately. Effects of a Bad Spark Plug: If the spark plug is damaged, it can directly cause issues such as leakage in the vehicle's ignition system, increased fuel consumption, and reduced power. The main problem is difficulty in ignition, affecting the normal use of the vehicle. Severe erosion of the spark plug, blistering at the top, damage, or melting and erosion of the electrode all indicate that the spark plug is ruined and should be replaced.