Spark plugs are responsible for making the fuel-air mixture in the cylinder chamber to explode and expand, creating the required mechanical power to keep the engine running on your car. If they get worn, the spark won’t be produced as effectively or won’t be produced at all, leading to power losses, increased fuel consumption and eventually to engine damage or even failure. Replacing your car’s spark plugs can be done easily at home and shouldn’t take more than an hour even for the most inexperienced.
1. Locate your spark plugs and disconnect spark wires
The location of the spark plugs main differ slightly between different engine types, but you won’t actually need a map to find them. On in-line 4 engines, spark plugs are usually placed on top or on the side of the engine. V8 and V6 engines will feature an equal number of spark plugs on each side of the engine.
Another way to find the spark plugs is by following the spark wires. They usually start from the same place and travel along the engine block, to the spark plugs. If you don’t see the end of the spark wires, you may need to remove the plastic engine cover before proceeding. This is usually done using a screwdriver. Just unscrew the bolts then remove the plastic engine cover. Disconnect the spark wires by pulling them out of the spark plugs.
2. Unscrew and replace the spark plugs
Next up, you need to unscrew the spark plugs. You will need either a 5/8 or 13/16 ratchet wrench along with an extension bar. Just plug the ratchet and then start unscrewing. The spark plugs may put a bit of a fight, but they should be next to impossible to remove. If that’s the case, then something may be wrong with them and a mechanic should be consulted.
Once you’ve gotten the spark plugs out, you should check their condition. If the ignition head is black, that’s a sign of oil consumption or high fuel consumption by the engine. You should check the oil gasket from the cylinder head for leaks, and replace it if that’s the case.
Put the old spark plugs away and screw in the new ones using the same ratchet and extension bar. Don’t go for extra tight screwing, just do it until it feels fixated, then push a little more.
3. Reattach spark wires
Now that spark plugs have been replaced, it is time to reconnect spark wires. It is critically important to reattach spark wires to their specific spark plugs. Otherwise, bad timing for the spark will result, damaging the internals of the engine. Usually, spark wires come in different lengths; the longest cable connects to the farthest spark plug, and so on.
Once you’ve set everything in place, start up your car and check if any warning lights are shown on the dashboard. If everything has been done right, the car should run smoother.