how to install spark plugs

How Often Should Spark Plugs Be Replaced?

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A single car has around 30,000 parts. Most drivers don't know the name of all of them; just the major ones yet motorists generally know the name of one of the car's smallest parts – the spark plug. That's because it's an important part of the car. Without it, your car wouldn't start as it delivers an electric current from the ignition system to the combustion chamber to ignite the air/fuel mixture in the engine. Do you know how often they need to be replaced or which spark plugs to use for your vehicle? Those questions along with a few others will be answered here.

When to Change Spark Plugs

You'll need to leave yourself around an hour to change the spark plugs on a typical four-cylinder engine. If you have the time and the confidence to change them yourself, your car will return better gas mileage and be at its peak performance. Over time spark plugs burn out but they last much longer than other parts of the car as most manufacturers recommend they're changed every 60,000 to 70,000 miles. You should get them checked every 30,000 miles though.

Engine Issues

The 2017 CarMD Vehicle Health Index shows that just over six percent of all engine-light related faults were caused by spark plug and ignition coil issues. Although spark plugs are small, when they fail they cause big issues. The engine may fail to start. If you get the car started, the engine might struggle to idle or it could stall from time to time for no obvious reason. Engine misfires and a lack of power under acceleration are other signs that the spark plugs need replacing. Thankfully it's not an expensive job if you choose to have it done by an expert.

Changing Spark Plugs

There are lots of little things that need to happen during the process of changing the spark plugs but let's not go into the details here. The best way of working out how to change the spark plugs is to take advice from someone who's done it before, whether that's through a mechanic you know or one that's uploaded a video online is up to you. The process basically involves disconnecting the spark plugs wires, removing the old plugs and replacing them with the new ones. Once you've reconnected the wires, you're back on the road.

Spark Plug Gapping

The gap between the side and center electrodes of each spark plug needs to be exactly the same for it to operate as it's designed to. As the plug ages and wears away, the gap widens. The extreme temperatures it works under, debris and wear and tear cause the gap to widen which makes combustion erratic and inefficient. You can adjust the gap between the electrodes in a process called gapping. You can find gap charts online or buy a spark plug gap tool if you're going to take care of this issue yourself.

Spark Plug Types

There's a wide variety of different spark plugs on the market. The plug's performance usually improves if you upgrade to something other than the basic copper plug. A platinum spark plug works in the same way as a copper one but it can last as much as 100,000 miles. Newer vehicles with electronic distributor-based ignition systems tend to have these installed. You also have to choice of installing Iridium coated plugs. Iridium is costly so expect to pay more for this type of plug but you will also get more for your money because the plug's fine wire center electrode helps increase firing efficiency.

Good to Know

Did you realize that cleaning your spark plugs can bring them back to their top performance? It's a time-consuming process and there's generally no need to do it though as new plugs are so cheap, you may as well replace them. When your plugs need changing, replace them for the manufacturer's recommended spark plugs. If you have to change the plugs, upgrading them to a platinum or iridium plug normally works fine but never downgrade them to copper.