How to Determine When Spark Plugs Need Replacement
2 Answers
Methods to determine when spark plugs need replacement: 1. Difficulty starting the vehicle: When the car has trouble starting, it may be due to excessive carbon buildup or other impurities on the spark plugs, causing the spark plug gap to widen; 2. Low engine power: This indicates excessive carbon deposits on the spark plugs, which reduces resistance during current distribution and affects the spark plugs, leading to insufficient engine power and reduced performance; 3. Excessive exhaust emissions: When spark plugs malfunction, they disrupt the normal operation of the ignition system, preventing the air-fuel mixture in the engine from burning completely. This results in harmful substances being emitted without full combustion, causing excessive exhaust emissions.
I've been fixing cars myself for many years, and there are several signs to determine if spark plugs need replacing. The engine feels sluggish when starting, like the battery is dead, the car shakes or vibrates noticeably during acceleration, and the tachometer needle jumps unsteadily at idle. Additionally, a sudden increase in fuel consumption—burning one or two extra liters per 100 kilometers—indicates incomplete combustion due to faulty spark plugs. While driving, always keep an eye on the engine warning light on the dashboard; if it comes on, it's time for a check-up. I often use simple tools to open the hood, pull out a spark plug, and inspect the electrode tip for wear or heavy carbon buildup. A healthy spark plug should be clean and unmarked, but cracks or discoloration mean it's time for a replacement. Generally, follow the vehicle manual's recommendation to inspect or replace spark plugs every 20,000 to 30,000 kilometers—don’t delay, or you might end up stranded with bigger problems. Developing a habit of regular maintenance can save you a lot of repair costs and time.
