The most likely culprit is what is known as the Spider Assembly or Fuel Injector Assembly it is located under the Plenum.
To Test you will need a fuel pressure tested. You will need to do a leak down test.
1) Connect the pressure tester. Place some rags or something to catch any gas that may spill
2) Have someone cycle the key to the on position Not Start/Run a few time to pressurize the system, check around the pressure tester to make sure of no leaks.
3) Pressurize the system again and Watch the gauge - one of 2 things will happen
1 - you will see a drop of 5 psi and then hold steady for at least 1 minute
2 - the gauge will drop to 0 psi
If the gauge drops to zero then most likely the Fuel Pressure Regulator is bad. And in order to verify you will have to remove the plenum.
Tuesday, January 20th, 2015 AT 8:29 PM