How to Replace Car Spark Plugs?
3 Answers
Steps for replacing spark plugs: Open the hood, lift the plastic engine cover, remove the high-voltage ignition wires, and mark each cylinder's position to avoid confusion. Use a spark plug socket to remove the spark plugs one by one. While removing, check for external debris like leaves or dust and ensure thorough cleaning. Place the new spark plug into the spark plug hole, hand-tighten it a few turns, then use the socket to tighten further. Reinstall the high-voltage ignition wires in the firing order and secure the cover. Spark plug replacement interval: Under normal maintenance conditions, replace every 40,000–60,000 km, but this may vary by brand and engine type. Always follow the owner's manual. Reference these general guidelines: Platinum spark plugs: replace at 40,000 km. Standard nickel-alloy spark plugs: replace at 20,000 km. Iridium spark plugs: replace at 60,000–80,000 km.
My experience with changing spark plugs is that the whole process requires careful attention. Prepare the tools: spark plug wrench, socket, gloves, and a rag. First, open the engine compartment and locate the spark plugs, usually on top of the engine cylinder head. Disconnect the ignition key to ensure the operation is done with the engine off. Carefully unscrew the connecting wire terminals one by one, don't mess around. Use the wrench to turn the old spark plugs counterclockwise and remove them, hold them steady to avoid dropping them into the cylinder. After taking out the new spark plugs, check the gap, usually 0.8 to 1.0mm is appropriate, measure it accurately with a small tool and don't be careless. Align and gently screw them into the hole clockwise, not too tight to avoid stripping the threads. Finally, reattach the wire terminals, start the car and listen for normal sounds. It's recommended to change them every 40,000 kilometers to keep the engine performance smooth, reduce carbon buildup issues, and improve fuel efficiency. The whole job takes about half an hour, but patience is key.
Safety must come first. Always disconnect the negative battery terminal before starting, and wear goggles and thick gloves to prevent electric shock and burns. The spark plug replacement process is most prone to dropping small objects into the cylinder, so I first use compressed air to blow away surrounding dust and debris. When removing the old plug, use a dedicated wrench with gentle motion to avoid damaging the threads. Before installing the new plug, verify its specifications match the vehicle model to prevent errors, and adjust the gap properly. The entire process should ideally be performed in a well-ventilated area, avoiding periods when the engine is hot to prevent accidents. Tightening torque should follow the manufacturer's manual, typically 15-20 Nm is sufficient - excessive force is dangerous. After replacement, test start the vehicle to ensure no abnormal sounds before shutting off the engine. Developing these habits can prevent risks and ensure smooth operation.
