What causes spark plug wear?
Without good spark plugs, your engine will not start. If even one plug fails, the change in functionality will be very noticeable. Your engine will sputter, it will idle poorly, it may spit and splatter…
Without good spark plugs, your engine will not start. If even one plug fails, the change in functionality will be very noticeable. Your engine will sputter, idle poorly, it may spit and rattle during acceleration, and it may even stall on you. Spark plugs wear out over time, although actual life varies depending on the type of plug, the condition of your engine, and your driving habits.
Spark plug wear factors
There are several factors that affect the performance of spark plugs, but the most common reason for spark plug wear is that they are simply old. To understand this, you need to know a little more about how spark plugs work.
When your generator generates electricity, it travels through the ignition system, through the spark plug wires, and to each individual spark plug. The candles then create electrical arcs on the electrodes (small metal cylinders protruding from the bottom of the candles). Each time the candle is lit, a small amount of metal is removed from the electrode. This shortens the electrode and requires more and more electricity to create the arc needed to ignite the cylinder. Eventually, the electrode will be so worn out that there will be no arc at all.
This is what happens in a normal, properly maintained engine. There are other factors that can shorten spark plug life (all spark plugs wear out over time; the only question is when).
Damage from overheating: Overheating the spark plugs can cause the electrode to wear faster. This can be caused by engine pre-ignition with incorrect timing, as well as an incorrect air-fuel ratio.
Oil contamination: If oil seeps onto the spark plug, it will contaminate the tip. This leads to damage and additional wear (oil seepage into the combustion chamber occurs over time as the seals begin to fail).
carbon: Carbon deposits on the tip can also lead to premature failure. This can happen due to dirty injectors, a clogged air filter, and many other reasons.
As you can see, there are a number of different factors that affect when your spark plugs fail and how useful they are to you.
