Symptoms of Bad or Failing Spark Plugs

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Nowadays, all drivers are concerned with their car’s fuel economy and achieving its maximum performance. They often blame bad gasoline, a poor repair job or other factors when things go wrong, but the cause could be much simpler and more innocent than they think. In fact, the leading cause of premature parts failures and costly repairs is lack of simple maintenance, and one specific area that is frequently overlooked is the ignition system. Common symptoms of ignition system failures include a rough idle, engine misfire, no-start condition, lack of power and many others. If these sound familiar, it might be time to check the ignition system, and one of the best places to start is with the spark plugs.

What should you know about spark plugs?

A spark plug serves one important purpose; it produces a high-voltage spark that ignites air/fuel in the engine, initiating the burning process of combustion and creating power. This is achieved by directing 12-volt electrical current from the battery and alternator through the ignition circuit and then sparking it across the electrodes at the end of the spark plug in the engine’s combustion chamber to ignite the air/fuel mixture. For spark plugs to operate correctly, they must be clean, receive current from the ignition system, and be properly installed.

What are symptoms of bad or failing spark plugs?

The most common symptom of spark plug malfunction is the one a driver hates most: poor performance. An engine with a rough idle or a misfire (where the engine shudders and RPM rises and falls) can be caused by a weak spark or a spark plug that is not firing at all. Common causes of a rough idle or misfire include an oil fouled spark plug, where oil has gotten into the combustion chamber, or a damaged spark plug wire that is no longer delivering current. Another cause is carbon fouling due to excessive fuel leftover in the cylinder after combustion, which can be caused by leaking fuel injectors or a restricted air intake manifold.

What should be done about bad spark plugs, or other ignition system problems?

If an ignition system problem is traced directly to a defective spark plug, it must be replaced, and while spark plugs vary in price based on their application, most run between $3-7 each. However, many spark plug problems such as oil or carbon fouling cannot be fixed simply by replacing the spark plugs, because another condition is causing the problem to occur. In these cases, it is necessary to consult an automotive technician to diagnose the source of the issue. Once the problem is resolved, the spark plugs can usually be cleaned and put back into service. If a more serious ignition problem is discovered, it might be time to replace other ignition system components.

Whatever parts your car might need, Gresham Auto Wrecking and Used Auto Parts has a fantastic selection at reasonable prices. Call us today for more information.