How to Measure the Condition of Spark Plugs?
1 Answers
Spark plugs exhibit the following symptoms when they may be faulty: Difficulty in starting the car, both cold and warm starts are challenging, often requiring multiple attempts. Engine shaking, noticeable vibrations while driving the car. Lack of power, a significant decrease in performance compared to normal conditions. Increased fuel consumption. Stalling. Failed emissions tests. Common causes and diagnosis of spark plug failures: Several common issues can prevent spark plugs from functioning properly: Incorrect spark plug gap adjustment. If the gap is too small, it limits the contact area between the spark and the air-fuel mixture and suppresses flame kernel growth due to the quenching effect of the electrodes. Even if a spark occurs, it is weak, making it difficult to ignite the mixture. If the gap is too large, the ignition system may not provide sufficient voltage to create a spark between the electrodes. Cracked spark plug skirt. High-voltage current can leak through the crack, preventing a spark from jumping between the electrodes. Electrode carbon buildup, causing the center electrode to leak current to the surroundings instead of jumping to the side electrode. Excessive carbon deposits can short-circuit the spark plug, preventing it from sparking, which may further damage the insulator and the spark plug itself. Damaged electrodes. Prolonged electrical erosion from sparks or chemical corrosion from combustion gases can cause the electrodes to break or fall off, preventing sparking. Low insulation resistance of the spark plug. This condition reduces the ignition voltage applied to the spark gap, weakening the spark or even completely disabling the ignition function. Short circuit in the high-voltage wires. If the high-voltage ignition wire from the ignition coil to the distributor leaks, the entire engine may fail to start. If the wire from the distributor to the spark plug leaks, the spark plug in one cylinder may not spark. Burnt platinum contacts. This can prevent all spark plugs from sparking, making the engine unable to start or run normally. Faulty spark plugs should be replaced promptly. The replacement steps are as follows: Open the hood, remove the plastic engine cover, and disconnect the high-voltage wires. Mark each cylinder's position to avoid confusion. Use a spark plug socket to remove the spark plugs one by one. Check for external debris like leaves or dust and clean thoroughly. Place the new spark plug into the spark plug hole, hand-tighten it a few turns, then use the socket to tighten it further. Reinstall the high-voltage wires in the correct firing order and reattach the cover. Spark plug replacement interval: Typically, spark plugs should be replaced every 40,000 to 60,000 kilometers under normal maintenance conditions. However, this may vary depending on the brand and engine type, so it's best to follow the manufacturer's manual.
