Common Signs of Bad Spark Plugs

row of spark plugs

The most common signs of bad spark plugs include start-up trouble, rough idling, sluggish acceleration, declining fuel economy, engine misfiring, and engine knocking. Failing to replace your spark plugs on schedule leads to poor performance in the short term, and potentially to serious damage in the long term, so don’t make the mistake of putting off service! If you’ve noticed any of the following signs and symptoms, schedule service and let us take a closer look today.

What Are the Signs That You Need New Spark Plugs?

Trouble Starting the Engine

In the worst of cases, you won’t notice the signs that you need new spark plugs until you’re stuck in your driveway with an engine that just won’t turn over! If your engine takes a long time to start or won’t start at all, your spark plugs may be to blame. Act quickly to have them replaced!

Rough Idling

So, you’ve managed to start your car—but now the motion of the engine sounds uneven, jittery, or rough. In addition to strange noises, an engine that isn’t idling properly may send noticeable vibrations throughout the vehicle. These vibrations can be disconcerting, to be sure, but they can also cause damage to sensitive components if left untreated.

Poor or Sluggish Acceleration

Your spark plugs ignite the fuel in your cylinders and force them into motion, and the energy produced by this process propels you forward on Los Gatos and Palo Alto roads. If you’re spending a longer time in the passing lane or you just can’t seem to get up to speed in short order, your spark plugs may be to blame.

Declining Fuel Economy

If your spark plug fails to ignite the fuel in the chamber, some or all of that fuel may go to waste. As a result, you’ll need to use more fuel to cover the same distance. You might only notice this issue if you’re spending more time—and more money—at the pump, but replacing your spark plugs can usually fix the problem right away.

Misfiring Engine

Maybe you won’t notice declining fuel economy or lackluster acceleration right away. However, you might still notice the cause of both these issues: engine misfiring. Misfiring is the common term for what happens when some or all of the fuel in the chamber fails to ignite. When combustion fails, you’ll notice that your engine cuts out momentarily or pulls you forward in a jerky, uneven way.

A misfiring engine must work harder and consume more fuel in order to deliver the power you need, resulting in declines to your vehicle’s fuel economy and performance. It can also lead to significant, lasting damage if the problem isn’t fixed.

Engine Knocking

Engine knocking can go hand-in-hand with engine misfiring, since the fuel that failed to ignite at the proper time will tend to combust later, when your engine isn’t ready for it. This error produces a distinct ‘knocking’ sound, so listen closely. If the problem is left untreated, it can damage your engine over time.

How Often Should You Change Your Spark Plugs?

Most experts recommend a spark plug replacement interval of 30,000 miles, or roughly once every two to three years. Schedule service if you’re due for replacement. Just make sure to check out our current service specials before you drive in from your home in San Francisco or San Jose.

Rely on Land Rover San Jose for Genuine Land Rover Parts!

If you’re in need of new spark plugs, you can rely on our team to get the job done right, and quickly! We carry out all work with genuine OEM parts, and that means you can count on our spark plugs to keep you moving forward. Contact us today if you have any questions about the signs of failing spark plugs.

Land Rover Service Coupons in San Jose

Land Rover Parts and Accessories Coupon in San Jose CA

Looking to enhance your Land Rover? Now you can get 10% off parts and accessories from Land Rover Stevens Creek. Located in San Jose, CA, we are near Los Gatos, Los Altos and Belmont.

*Plus tax and applicable fees. Must present coupon at time of write-up. Cannot combine with any other offer or discount. Limit one coupon per visit. Coupon does not apply to prior purchase. See your service adviser for details. Capped at $150 off.
Not valid with any other offers.

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