7 Signs You Need to Replace Your Spark Plugs
The car is hard to start. The engine misfires. You’re heading to the gas station more often. The engine idling is rough and noisy. Your car struggles to accelerate. The engine is really loud during normal driving. Your ‘check engine’ light is on.

What does it feel like when spark plugs are bad?

Common signs of faulty spark plugs include slow acceleration, loss of power, poor fuel economy, engine misfires, and difficulty starting the car.

How much does it cost to fix spark plugs?

The Average Cost to Replace Spark Plugs Is $66-$250, Depending on if You Go to the Mechanic or DIY. This price range is based on national averages for all vehicles and does not factor in taxes, fees, or your particular make and model.

Do spark plugs affect acceleration?

And because spark plug health is directly linked to engine performance, it stands to reason weak or bad spark plugs lead to problems, be it issues with cold-starting or misfires during acceleration. Besides—without healthy ones—your ride can’t sustain maximum power, and your vehicle can see a drop in fuel economy.

What does engine misfire feel like?

When a misfire occurs, you may feel like light or strong jerk coming from the engine. These misfires do often come under load from the engine, like when you are accelerating hard. The most common situation to notice misfires is on high gears, low RPM, and the accelerator to the floor.

Can I replace spark plugs on my own?

Changing spark plugs takes about an hour (for a four-cylinder engine) and will save you at least a hundred bucks in labor if you do it yourself. In most cases it’s a simple job that will help to maintain peak performance and the highest possible gas mileage.

How often should you replace your spark plugs?

Spark plugs are somewhat durable components and don’t need to be replaced too often, that said, the general recommendation is about every 30,000 to 90,000 miles. Each vehicle may differ on when they should be replaced.

Does AutoZone install spark plugs?

AutoZone doesn’t change spark plugs for its customers in 2022. As an auto store, it might not provide mechanic services, but will refer you to other service providers such as Walmart that can change them.

What does a weak spark look like?

A good spark will be blue-white and will be plainly visible in daylight. If a good spark is present, the problem is probably not in the ignition system. Check the fuel system and/or stark timing. Weak sparks are orange or red and may be hard to see in daylight.

How do I test a spark plug?

Test with a spark plug tester
Attach a spark plug tester to the ignition wire. At the other end, the tester connects to the spark plug as it sits in your engine.Turn the ignition ON.Start the engine, or simply turn it over if it won’t start, and watch the transparent sides of the tester.

What color should the spark be?

On an automobile ignition system the spark should be bright blue. That’s because the compression ratio is higher than that on an air cooled small engine.