Why does a 1998 Camry 4-cylinder sometimes not start when you turn the key though it may start after 3-4 tries?

your igniter is the least common thing to check if your car wont start. check your fuel pump first. their are three things that can cause it to do that. your fuel, ignition, or your compression. an igniter with run you over 150 dollars. start with the small inexpensive stuff first. buy or rent a fuel pressure gauge and check your pressure. if that's ok then check to see if you have spark from your spark plug wires. if you have spark and fuel then the only thing left is compression. rent a compression kit and check that.