Too Wide a Gap:
* Misfires: This is the most common problem. A wider gap requires a stronger spark to jump the distance. If the voltage isn't sufficient (due to weak coil, low compression, etc.), the spark will fail to ignite the air/fuel mixture consistently. This leads to misfires, resulting in:
* Rough idling: The engine will run unevenly and shake.
* Poor acceleration: The engine will hesitate or struggle to accelerate smoothly.
* Reduced fuel economy: Unburnt fuel is wasted.
* Check engine light: The car's computer will detect misfires and illuminate the check engine light.
* Damage to the catalytic converter: Unburnt fuel entering the exhaust system can overheat and damage the catalytic converter.
Too Narrow a Gap:
* Pre-ignition (or detonation): A narrower gap can cause the spark to occur too early, before the piston is optimally positioned. This can lead to:
* Knocking or pinging: A metallic pinging sound from the engine.
* Engine damage: Pre-ignition can generate excessive heat and pressure, potentially damaging pistons, connecting rods, and bearings.
* Reduced engine life: Consistent pre-ignition will shorten the lifespan of your engine.
* Fouling: A narrower gap can lead to increased fouling, which is the build-up of carbon and deposits on the spark plug. Fouling can make the spark plug non-functional.
In short: The correct spark plug gap is crucial for optimal engine performance and longevity. Using the wrong gap compromises ignition efficiency, leading to a range of problems from minor annoyances to costly engine repairs. Always refer to your vehicle's owner's manual or a reliable source (like a repair manual specific to your car's make and model) for the correct gap specification.
