I have a 04' f250 with a late 03' 6.0 motor in it. It has an egr delete an i replaced the irp sensor. Its running ruff and will not start after its warmed up until i turn the key on/off several times. I know i need a injector an i want to stay with stock injectors. where can i find good priced stock injectors? The second question is could the dummy plugs be bad, Is that the reason why it won't start after its warm?