- Dirty spark plugs cause misfiring, power loss, hard starts, and higher fuel consumption
- Types of fouling include oil, gasoline, carbon, and burnt electrode deposits
- Clogged air filters reduce oxygen, causing rich mixtures and spark plug deposits
- Follow service intervals and replace air filters to prevent costly repairs
Spark plugs are essential components for the operation of a spark-ignition engine. Without a spark, the fuel-air mixture will never ignite, meaning your car won’t start without functional spark plugs. These components receive a high-voltage current at one end and ignite the mixture with the spark at the other.
For optimal performance, the terminal that emits the spark must always be clean. When this tip becomes dirty, it will directly affect how the engine runs.
Types of spark plug fouling
A dirty spark plug can exhibit different types of deposits:
- Oil – resulting from wear of piston rings or valve guides
- Gasoline – caused by a fuel mixture that is too rich
- Carbon deposits – formed from incomplete combustion of the fuel
- Burnt electrode – when the engine runs for too long with an overheating engine/condition
Symptoms of a misfiring engine
When spark plugs are dirty or faulty, the engine will show several characteristic problems:
Increased fuel consumption
First, the car’s fuel consumption rises. The engine will try to compensate for the loss of power by injecting more fuel into the mixture, disturbing the optimal air-fuel ratio.
Power loss and performance
The car won’t pull like before, because the combustion in the cylinder no longer follows the engine manufacturer’s prescribed parameters. Acceleration becomes slow and strained.
Starting problems
The engine will start hard not only in the morning, but every time you try to start it. You’ll notice the engine no longer starts “on a quarter” and will require more attempts.
Uneven operation
Over time, the engine will misfire, lose power during acceleration, stumble, and may eventually run on only three cylinders instead of four.
The unexpected link: the air filter and spark plugs
It may seem odd, but spark plugs can fail due to a dirty air filter. When the filter is clogged, the engine no longer receives enough oxygen for a complete burn.
Deterioration process
- Oxygen reduction: The engine is no longer sufficiently oxygenated
- Rich mixture: More fuel enters the air-fuel mixture, occupying the oxygen’s place
- Incomplete combustion: This overly fuel-rich combustion creates large amounts of carbon
- Deposits on the spark plugs: Carbon gradually deposits on the tip of the spark plug [spark plug], ultimately damaging it
Importance of preventive maintenance
A simple air filter that costs only a few tens of lei can affect the entire engine if not replaced on time. Therefore, it is essential to:
- Follow service intervals
- Replace the air filter according to the maintenance schedule
- Periodically check the condition of the spark plugs
- Perform all necessary replacements on time
Preventive maintenance is always cheaper than major repairs that can result from neglecting seemingly minor engine components.
Photo source: lmr.com, mechanics.stackexchange.com
