5.3 with stage 2 cam running extremely

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I have a 5.3 with a Summit Truck stage 2 cam, flat top pistons, TBSS intake manifold, 92mm throttle body. The truck was running great i was logging the MAF to make adjustments and then I noticed bank 2 O2 sensor output in the teens and then bank 1 O2 sensor going in the teens and my wideband was passed 18. I replaced my fuel pump have 55 psi at the regulator with the same results. Checked each fuel injector with a noid light all were receiving a signal. Replaced the fuel injectors same result. I am getting a P0200 fault and replaced the ECM with a clone ECM. I do not know what else to check or replace 7242 2003 tahoe 3-22-24 MOT3.hpt24-03-23 18-30-42.hpl24-03-10 18-11-04.hpl

[ns158sl]

Wiring or fuel injectors

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Fuel psi under load? Flow test on fuel system? Injector duty cycle? Excessive air leak before or near o2 sensors? Mechanical issues with engine, broken valve spring or the like.