2001 Mitsubishi Mirage #2 cylinder misfire code

Hey guys,

I have a 2001 Mitsu Mirage, bout 150,000 mile. bout a week ago the engine started to stutter I took it to a auto parts store to put the diagnostic meter on it. It read that the #2 cylinder was misfiring. I started small and got bigger in my troubleshooting.
1. Changed plugs and wires
2. Changed coil packs
3. replaced fuel injectors
Now, I'm not sure what to do, any advice would be great thanks.

Jonathan