What Are the Symptoms of Aging Car Spark Plugs?
3 Answers
The symptoms of aging car spark plugs include: 1. Increased deposits inside the spark plug; 2. Melting or burning of the electrodes; 3. Malfunction of the ignition system; 4. Reduced power and sluggish acceleration; 5. Severe idle vibration; 6. Difficulty starting or sudden engine stalling. The effects of aging spark plugs: 1. Lower power output, reduced shunt resistance, unstable engine operation, leading to weak throttle response; 2. Significant car vibration during idle; 3. Increased exhaust emissions and higher fuel consumption. The function of car spark plugs is to receive high-voltage electricity from the ignition system, create an electric spark by ionizing the air between the electrodes, and ignite the air-fuel mixture in the cylinder.
I've been driving for decades. When spark plugs age, they make the car shake violently, especially at idle while waiting at a red light—it feels like an earthquake. Starting the car also becomes difficult; on winter mornings, it takes several attempts. Fuel consumption spikes dramatically—a full tank that used to last 500 kilometers now runs dry before even 400. Acceleration becomes sluggish, and climbing hills is a struggle. A friend taught me to check the spark plug gap—if it's widened, it means they're worn out, causing misfires and black smoke from unburned fuel. Just replace them every 20,000 kilometers as routine maintenance—don't wait until the engine light comes on to fix it, or the engine damage will be worse.
Right after I got my driver's license, I encountered an issue with aging spark plugs—the car's idle was as unstable as dancing, shaking upon startup. Acceleration became snail-like, with no response when stepping on the gas. Fuel consumption skyrocketed, hurting my wallet. Later, the engine light came on, and at the repair shop, the mechanic said the spark plugs were severely carbon-fouled, failing to ignite properly, causing idle vibrations and smoke from the exhaust pipe. Replacing them immediately smoothed things out. I recommend checking spark plugs every three to four years to prevent small issues from turning into big troubles.
