DIY, change the spark plugs on your Toyota Camry made in the year 1998. To complete this repair you will require four new spark plugs from your local auto parts shop and a 5/8 spark plug wrench, with an extension. This is the kind of repair that you can do it by yourself in about 20 minutes.
You can begin the repair by opening the hood of your car and by disconnecting the negative cable from the battery. It is recommended to do so, in order to avoid unwanted electrical accidents, shortcuts or errors on the computer. Now, locate the spark plug cables on top of the engine (see next picture) and unplug one of them. Just pull it up and remove in this way the connection to the spark plug.
At this moment you have access to the spark plug and you can replace it using the 5/8 wrench (see image below). It is better to remove the connections one by one, because that way there is no chance of confusing the wires when you reconnect everything back. Repeat the process on each of the four spark plugs.
After you replace all the spark plugs and plug back the connections, at the end you just have to reconnect the negative cable on the battery and you are done. This is all you need to do if you need to change the spark plugs on your Toyota Camry made in the year 1998.