Spark plugs should be replaced in line with the manufacturer's service schedule. Most manufacturers recommend spark plugs to be changed every 30,000 to 50,000 km, but this is the maximum duration, spark plugs can and do fail at any time. Spark plugs cost very little compared to other components.
Ordinary copper and nickel spark plugs should be changed every 30,000 to 50,000 miles, unless otherwise suggested by the spark plug manufacturer. Platinum and iridium spark plugs tend to last longer than standard copper and nickel spark plugs. Expect to change them every 60,000 to 150,000 miles unless otherwise noted.
The most common signs of bad spark plugs include start-up trouble, rough idling, sluggish acceleration, declining fuel economy, engine misfiring, and engine knocking.
Most manufacturers recommend replacing spark plugs every 50,000 kilometres, but spark plug quality varies. Some last around 130,000 kilometres, while cheap plugs made of copper may last approximately 40,000 kilometres. “Extended life” spark plugs made of more resilient metals can last up to 160,000 kilometres.
Standard copper spark plugs last around 20,000 – 30,000 kms. The spark plugs play an important role in your engine, they produce electrical sparks that ignites the mixture of fuel and air in your engine's combustion chambers, causing the pistons to move up and down.
Luckily, spark plugs don't require replacement very often and can go years and many miles before replacement is needed.
The spark plugs in many vehicles today have iridium or platinum tips on the electrodes (the parts that transmit the spark) that last longer than conventional plugs with copper and nickel-alloy electrodes.
NGK gives them a life expectancy of 40-50k miles. But they have to temper their projections as driving conditions and motor modifications differ. Typically we have found you can expect 60,000 to 80,000 miles on an unaltered motor. NGK Laser Iridium Spark Plugs have iridium center and a platinum ground electrodes.
Even the sharpest of all tools wears out eventually. Same is applicable to our beloved spark plugs. Getting premium spark plugs to have a wide array of benefits such as better fuel efficiency, reduced emissions and improved overall longevity of the engine. But all things age with time, and so do the spark plugs.
If you let your spark plugs go for too long, you could do some severe damage to your engine. The deposits that build upon the plugs can eventually cause them to misfire. When this happens, the unburned fuel in the cylinders can start to eat away at the cylinder walls.
Over time, they get worn or build up deposits from years of use and they become less effective and efficient. I have rarely ever heard of a spark plug failing 100% all of a sudden. Over time, it would contribute to reduced gas mileage, rough idle, and sluggish performance.
Whenever you change spark plugs, it is a good idea to replace the ignition wires and vice versa. This will keep your vehicle running at peak performance and prevent you wasting money on unburned gasoline. In fact, a sudden drop in gas mileage may be an indicator that your ignition system is not functioning properly.
To go along with engine fit, most spark plugs get made from different types of metal, some being cheaper than others. However, cheap ones tend to last a shorter lifespan than ones made from more expensive metals. Manufacturers will typically recommend the type of spark plugs your gas-powered vehicle needs.
Generally speaking, it is wise to change all of your spark plugs at once. Unless one of your spark plugs has become badly damaged or broken, replacement of all plugs at once will help to ensure consistent levels of performance in your engine.
A leading cause of spark plug problems is a flow of engine oil into the combustion chamber. If oil leaks into the combustion chamber, it can cause the tip of the spark plug to get oily and dirty leading to premature failure.
Factoring in parts and labor, the cheapest spark plug replacement costs between $100 and $250, and the highest is between $250 and $500. It is ideal to replace all spark plugs at once to avoid dealing with different replacement cycles and to achieve optimum performance.
And we can't overlook the pure alumina silicate ceramic insulator, which provides unmatched strength and heat resistance that give NGK spark plugs a reliable reputation.
The estimated mileage of iridium spark plugs – depending on the thickness of the central electrode and the construction of the ground electrode – ranges from 60,000 km up to 120,000 km in the case of DENSO Super Ignition Spark Plugs, which feature a protruding ground electrode, like DENSO's Twin Tip (TT) Spark Plugs.
At the top of the list, we have the NGK Spark Plugs. With iridium as its core material, this spark plug pack can operate at a much wider heat range as compared to ordinary spark plugs made out of platinum or copper.
Platinum is much harder metal than nickel alloy and has a higher melting point. Since platinum is harder, it holds its sharp edge much longer than a conventional spark plug, up to 100,000 miles. Longevity is a key advantage of platinum spark plugs.
Longevity is a key advantage in platinum spark plugs — they're typically replaced around 60,000 miles but can last up to 100,000 miles. And because platinum can handle a high heat range, combustion deposits burn off better, preventing spark plug fouling.