Need solution to piston misfire

[dbwilder22]

Hello everyone,
First, I am brand new to the forum and would like to thank you for providing the space.
Second, I am an absolute novice to working on my car. I am just now learning and have found it difficult to learn everything on the boxer engine. With that being said I need professional opinion on what is wrong with my car. I'll provide a breakdown of the issues and everything I have done.

I received the car from my parents in August last summer. When I got the car, the engine was shaking while idle, and the check engine light was on. They lived in Kentucky and I drove it across the country to Denver, without having it looked at.

I have been working in Golden and have been driving it back and forth 5 days a week. After a while the car began dying as I let off the gass pedal and decelerated, and throughout this time the idle became rougher and rougher.

I took it to an auto parts store and ran a check on the computer and found that piston #2 and #4 are misfiring.

I have
- changed spark plugs
- changed air filter
- changed the fuel injectors on the driver side
- changed the oil

I have done the only basic things I know in order to find a solution. I am at a completely loss at what could be causing the problem. These are also the systems.

- Easy when engine hasn't been started all day
- Rough idle
- Low RPMS.
- Only dies after applying gas pedal

The car is a 2006 subaru baja turbo. It is a 2.5 L 4 Cylinder engine. It has a little over 100,000 miles on it.

Any knowledge would be MUCH appreciated.