spark plugs

“Spark plug” is a word you are likely familiar with; it’s one of those car terms that you’ve heard your whole life. You know they’re important, you know sometimes they need to be changed. But how do you know when it’s time to replace them? What do they do, and where do they go wrong? Harold's Used Auto Parts Inc in Philadelphia has the answers.

Your spark plugs are an essential part of your engine. While much of car technology has improved, and old technology has been replaced, spark plugs have remained integral and virtually unchanged since the beginning.

The spark plug is a simple mechanism with a simple job - two points, with a gap in between them, cause an electrical charge to jump across the gap, igniting the fuel in your cylinder at just the right moment, creating the combustion in your engine which powers your car. Essentially, the spark plug creates a spark that ignites the gasoline. Changing spark plugs used to be an easy maintenance item that anyone could do at home. However, with the advent of v-shaped engines, front-wheel-drive cars, aluminum heads, and engine positions that aren’t exactly conducive to easy maintenance, the job has become a bit more technical on many modern vehicles.

A simple job that took your grandpa 20 minutes in the 1950s, has transformed into one which may require the removal of a wheel, special tools, certain techniques, and runs the risk of stripping out the spark plug hole or damage to other components. What this also means is spark plugs have become a maintenance item people often neglect, running the same spark plugs well after their time has expired. Another common issue is as follows: a home mechanic begins replacing spark plugs, eventually runs into one that is too difficult to remove, and opts to just change all the easy ones. When someone checks the plugs to see if they have been replaced, they too check the easy ones, see that they are new, and assume all of them have been replaced. Now the vehicle has mostly new plugs, and one hidden plug in a dark recess of the engine compartment that desperately needs replacing. Since the other plugs are new, the engine will probably keep running, but will exhibit signs of a problem.

So how do you know if your plugs need to be changed? Low power, engine vibration, or a check engine light are all signs that one or more spark plug needs to be replaced. Even if your car runs well, it may be time for a replacement - once the plugs wear down or corrode, the spark weakens, and your engine suffers a slow decrease in performance that you may not notice over time. Plugs can also crack or break internally, rendering them useless. If your car is running poorly, your spark plugs may be the culprit. If your car is overdue for a factory recommended spark plug change, or you aren’t sure when they were changed last, it’s time to at least have them inspected.

The bottom line is that spark plug maintenance is essential. They are cheap, and to a professional with the right equipment, they are also easy to change. If your car isn’t performing like you think it could, or you are overdue for new plugs, let one of our expert technicians at Harold's Used Auto Parts Inc take a look. We can tell you if they need to be replaced, and to the trained eye, a spark plug is also an indicator of how well your engine is performing. If it is time to replace them, we’ll handle that too. Trust Harold's Used Auto Parts Inc to keep your engine running smoothly and your mind at ease.



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5347 Whitby Ave
        Philadelphia, PA

(215) 472-1552
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MON-FRI | 8:30 AM - 5:30 PM
SAT | 8:30 AM - 2:00 PM
SUN | CLOSED
Closed every third Saturday of the month