I've already looked into that. Fuel pressure is good, timing is good, all of the injectors appear to be working fine. I may send them back to get tested and inspected though just to be sure. But I think they are okay. This is a new engine as of early this year, new fuel pump and filter, injectors are flow matched bosch type 3 32lb rebuilt from fuel injection connection. And how do you explain my tune changing and going lean some days and then not being able to fix it unless I retune my fuel maps or reflash the chip? Then a few weeks later I have to do it again.